Add/move/fix default data methods of all entities

* Keys.POTION_EFFECTS now always present, but may be empty
* Do not consider ourselves as a base vehicle

src/main/java/org/spongepowered/api/data/Keys.java

@@ -443,7 +443,7 @@ public final class Keys {
 
     /**
      * The {@link BossBar} displayed to the client by a {@link Boss}.
-     * Readonly but mutable?
+     * TODO Readonly but mutable?
      */
     public static final Key<Value<BossBar>> BOSS_BAR = Keys.key(ResourceKey.sponge("boss_bar"), BossBar.class);
 
@@ -603,11 +603,11 @@ public final class Keys {
     public static final Key<Value<SpellType>> CURRENT_SPELL = Keys.key(ResourceKey.sponge("current_spell"), SpellType.class);
 
     /**
-     * The damage dealt towards entities of a specific {@link EntityType} by a {@link DamagingProjectile}.
+     * The damage dealt towards entities of a specific {@link EntityType} by a {@link ArrowEntity}.
      *
      * <p>Note that in events, the damage defined for the provided
      * {@link EntityType} will take priority over the "default" damage as
-     * defined from {@link DamagingProjectile#attackDamage()}.</p>
+     * defined from {@link ArrowEntity#attackDamage()}.</p>
      *
      * <p>Types not present in this mapping will be
      * dealt damage to according to {@link #ATTACK_DAMAGE}.</p>
@@ -2585,7 +2585,7 @@ public final class Keys {
     public static final Key<Value<Boolean>> TRACKS_OUTPUT = Keys.key(ResourceKey.sponge("tracks_output"), Boolean.class);
 
     /**
-     * Tge {@link TradeOffer}s offered by a {@link Trader}.
+     * The {@link TradeOffer}s offered by a {@link Trader}.
      */
     public static final Key<ListValue<TradeOffer>> TRADE_OFFERS = Keys.listKey(ResourceKey.sponge("trade_offers"), TradeOffer.class);
 

src/main/java/org/spongepowered/api/entity/AreaEffectCloud.java

@@ -128,14 +128,4 @@ public interface AreaEffectCloud extends Entity {
     default ListValue.Mutable<PotionEffect> effects() {
         return this.requireValue(Keys.POTION_EFFECTS).asMutable();
     }
-
-    /**
-     * {@link Keys#AGE}
-     *
-     * @return The age of this cloud
-     */
-    default Value.Mutable<Integer> age() {
-        return this.requireValue(Keys.AGE).asMutable();
-    }
-
 }

src/main/java/org/spongepowered/api/entity/Entity.java

@@ -31,6 +31,7 @@ import net.kyori.adventure.text.event.HoverEventSource;
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.SerializableDataHolder;
 import org.spongepowered.api.data.value.ListValue;
+import org.spongepowered.api.data.value.SetValue;
 import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.event.cause.entity.damage.source.DamageSource;
 import org.spongepowered.api.projectile.source.EntityProjectileSource;
@@ -376,7 +377,7 @@ public interface Entity extends Identifiable, HoverEventSource<HoverEvent.ShowEn
      *
      * @return The "base vehicle" of the entity vehicle riding chain
      */
-    default Optional<Value.Mutable<Entity>> baseVehicle() {
+    default Optional<Value<Entity>> baseVehicle() {
         return this.getValue(Keys.BASE_VEHICLE).map(Value::asMutable);
     }
 
@@ -385,7 +386,7 @@ public interface Entity extends Identifiable, HoverEventSource<HoverEvent.ShowEn
      *
      * @return Whether this entity is on the ground
      */
-    default Value.Mutable<Boolean> onGround() {
+    default Value<Boolean> onGround() {
         return this.requireValue(Keys.ON_GROUND).asMutable();
     }
 
@@ -437,7 +438,7 @@ public interface Entity extends Identifiable, HoverEventSource<HoverEvent.ShowEn
     /**
      * {@link Keys#FIRE_TICKS}
      *
-     * @return The amount of time in ticks an Entity is will continue burn for.
+     * @return The amount of time in ticks the entity is will continue burn for
      */
     default Optional<Value.Mutable<Ticks>> fireTicks() {
         return this.getValue(Keys.FIRE_TICKS).map(Value::asMutable);
@@ -446,10 +447,10 @@ public interface Entity extends Identifiable, HoverEventSource<HoverEvent.ShowEn
     /**
      * {@link Keys#FIRE_DAMAGE_DELAY}
      *
-     * @return The amount of time to delay in ticks before an Entity will be burned by fire.
+     * @return The amount of time to delay in ticks before the entity will be burned by fire
      */
-    default Optional<Value.Mutable<Ticks>> fireImmuneTicks() {
-        return this.getValue(Keys.FIRE_DAMAGE_DELAY).map(Value::asMutable);
+    default Value.Mutable<Ticks> fireImmuneTicks() {
+        return this.requireValue(Keys.FIRE_DAMAGE_DELAY).asMutable();
     }
 
     /**
@@ -457,8 +458,197 @@ public interface Entity extends Identifiable, HoverEventSource<HoverEvent.ShowEn
      *
      * @return The transient state
      */
-    default Optional<Value.Mutable<Boolean>> isTransient() {
-        return this.getValue(Keys.TRANSIENT).map(Value::asMutable);
+    default Value.Mutable<Boolean> isTransient() {
+        return this.requireValue(Keys.TRANSIENT).asMutable();
+    }
+
+    /**
+     * {@link Keys#AGE}
+     *
+     * @return The age of this entity
+     */
+    default Value.Mutable<Integer> age() {
+        return this.requireValue(Keys.AGE).asMutable();
+    }
+
+    /**
+     * {@link Keys#BASE_SIZE}
+     *
+     * @return The base size of the entity
+     */
+    default Value<Double> baseSize() {
+        return this.requireValue(Keys.BASE_SIZE);
+    }
+
+    /**
+     * {@link Keys#EYE_HEIGHT}
+     *
+     * @return The height of the eyes
+     */
+    default Value<Double> eyeHeight() {
+        return this.requireValue(Keys.EYE_HEIGHT);
+    }
+
+    /**
+     * {@link Keys#EYE_POSITION}
+     *
+     * @return The position of the eyes
+     */
+    default Value<Vector3d> eyePosition() {
+        return this.requireValue(Keys.EYE_POSITION);
+    }
+
+    /**
+     * {@link Keys#HEIGHT}
+     *
+     * @return The height of the entity
+     */
+    default Value<Double> height() {
+        return this.requireValue(Keys.HEIGHT);
+    }
+
+    /**
+     * {@link Keys#INVULNERABILITY_TICKS}
+     *
+     * @return The amount of ticks the entity will remain invulnerable for
+     */
+    default Value.Mutable<Ticks> invulnerabilityTicks() {
+        return this.requireValue(Keys.INVULNERABILITY_TICKS).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_CUSTOM_NAME_VISIBLE}
+     *
+     * @return Whether a custom name is visible on the entity
+     */
+    default Value.Mutable<Boolean> customNameVisible() {
+        return this.requireValue(Keys.IS_CUSTOM_NAME_VISIBLE).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_GLOWING}
+     *
+     * @return Whether the entity has a glowing outline
+     */
+    default Value.Mutable<Boolean> glowing() {
+        return this.requireValue(Keys.IS_GLOWING).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_INVISIBLE}
+     *
+     * @return Whether the entity is currently invisible
+     */
+    default Value.Mutable<Boolean> invisible() {
+        return this.requireValue(Keys.IS_INVISIBLE).asMutable();
+    }
+
+    /**
+     * {@link Keys#INVULNERABLE}
+     *
+     * @return Whether the entity is invulnerable
+     */
+    default Value.Mutable<Boolean> invulnerable() {
+        return this.requireValue(Keys.INVULNERABLE).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_SNEAKING}
+     *
+     * @return Whether the entity is sneaking
+     */
+    default Value.Mutable<Boolean> sneaking() {
+        return this.requireValue(Keys.IS_SNEAKING).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_SPRINTING}
+     *
+     * @return Whether the entity is sprinting
+     */
+    default Value.Mutable<Boolean> sprinting() {
+        return this.requireValue(Keys.IS_SPRINTING).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_WET}
+     *
+     * @return Whether the entity is wet
+     */
+    default Value<Boolean> wet() {
+        return this.requireValue(Keys.IS_WET).asMutable();
+    }
+
+    /**
+     * {@link Keys#MAX_AIR}
+     *
+     * @return The max air supply
+     */
+    default Value.Mutable<Integer> maxAir() {
+        return this.requireValue(Keys.MAX_AIR).asMutable();
+    }
+
+    /**
+     * {@link Keys#REMAINING_AIR}
+     *
+     * @return The remaining air supply
+     */
+    default Value.Mutable<Integer> remainingAir() {
+        return this.requireValue(Keys.REMAINING_AIR).asMutable();
+    }
+
+    /**
+     * {@link Keys#SCOREBOARD_TAGS}
+     *
+     * @return The scoreboard tags applied to the entity
+     */
+    default SetValue.Mutable<String> scoreboardTags() {
+        return this.requireValue(Keys.SCOREBOARD_TAGS).asMutable();
+    }
+
+    /**
+     * {@link Keys#VANISH}
+     *
+     * @return Whether the entity is vanished
+     */
+    default Value.Mutable<Boolean> vanish() {
+        return this.requireValue(Keys.VANISH).asMutable();
+    }
+
+    /**
+     * {@link Keys#VANISH_IGNORES_COLLISION}
+     *
+     * @return Whether the entity ignores collision with other entities
+     */
+    default Value.Mutable<Boolean> vanishIgnoresCollision() {
+        return this.requireValue(Keys.VANISH_IGNORES_COLLISION).asMutable();
+    }
+
+    /**
+     * {@link Keys#VANISH_PREVENTS_TARGETING}
+     *
+     * @return Whether the entity can be targeted for attack by another entity
+     */
+    default Value.Mutable<Boolean> vanishPreventsTargeting() {
+        return this.requireValue(Keys.VANISH_PREVENTS_TARGETING).asMutable();
+    }
+
+    /**
+     * {@link Keys#CUSTOM_NAME}
+     *
+     * @return The custom name of the entity
+     */
+    default Optional<Value.Mutable<Component>> customName() {
+        return this.getValue(Keys.CUSTOM_NAME).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#SWIFTNESS}
+     *
+     * @return The current swiftness of the entity
+     */
+    default Optional<Value.Mutable<Double>> swiftness() {
+        return this.getValue(Keys.SWIFTNESS).map(Value::asMutable);
     }
 
     @Override

src/main/java/org/spongepowered/api/entity/FallingBlock.java

@@ -38,7 +38,7 @@ public interface FallingBlock extends Entity {
     /**
      * {@link Keys#BLOCK_STATE}
      *
-     * @return The blockstate
+     * @return The block state of the falling block
      */
     default Value.Mutable<BlockState> blockState() {
         return this.requireValue(Keys.BLOCK_STATE).asMutable();

src/main/java/org/spongepowered/api/entity/Item.java

@@ -29,6 +29,7 @@ import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.item.ItemType;
 import org.spongepowered.api.item.inventory.ItemStack;
 import org.spongepowered.api.item.inventory.ItemStackSnapshot;
+import org.spongepowered.api.util.Ticks;
 
 /**
  * Represents an Item.
@@ -43,4 +44,40 @@ public interface Item extends Entity {
     default Value.Mutable<ItemStackSnapshot> item() {
         return this.requireValue(Keys.ITEM_STACK_SNAPSHOT).asMutable();
     }
+
+    /**
+     * {@link Keys#DESPAWN_DELAY}
+     *
+     * @return The despawn delay (in ticks) of the item
+     */
+    default Value.Mutable<Ticks> despawnDelay() {
+        return this.requireValue(Keys.DESPAWN_DELAY).asMutable();
+    }
+
+    /**
+     * {@link Keys#INFINITE_DESPAWN_DELAY}
+     *
+     * @return Whether the item will not despawn for an infinite time
+     */
+    default Value.Mutable<Boolean> infiniteDespawnDelay() {
+        return this.requireValue(Keys.INFINITE_DESPAWN_DELAY).asMutable();
+    }
+
+    /**
+     * {@link Keys#INFINITE_PICKUP_DELAY}
+     *
+     * @return Whether the item has an infinite pickup delay
+     */
+    default Value.Mutable<Boolean> infinitePickupDelay() {
+        return this.requireValue(Keys.INFINITE_PICKUP_DELAY).asMutable();
+    }
+
+    /**
+     * {@link Keys#PICKUP_DELAY}
+     *
+     * @return The pickup delay (in ticks) of the item
+     */
+    default Value.Mutable<Ticks> pickupDelay() {
+        return this.requireValue(Keys.PICKUP_DELAY).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/explosive/EndCrystal.java

@@ -52,4 +52,13 @@ public interface EndCrystal extends Explosive {
     default Value.Mutable<Boolean> showBottom() {
         return this.requireValue(Keys.SHOW_BOTTOM).asMutable();
     }
+
+    /**
+     * {@link Keys#HEALTH}
+     *
+     * @return The health of the end crystal
+     */
+    default Value.Mutable<Double> health() {
+        return this.requireValue(Keys.HEALTH).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/explosive/fused/FusedExplosive.java

@@ -52,4 +52,13 @@ public interface FusedExplosive extends Explosive {
     default Value.Mutable<Ticks> fuseDuration() {
         return this.requireValue(Keys.FUSE_DURATION).asMutable();
     }
+
+    /**
+     * {@link Keys#TICKS_REMAINING}
+     *
+     * @return The remaining fuse time in ticks of the fused explosive
+     */
+    default Value.Mutable<Ticks> ticksRemaining() {
+        return this.requireValue(Keys.TICKS_REMAINING).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/explosive/fused/PrimedTNT.java

@@ -37,7 +37,8 @@ public interface PrimedTNT extends FusedExplosive {
 
     /**
      * {@link Keys#DETONATOR}
-     * @return The living entity that primed this tnt
+     *
+     * @return The living entity that primed this TNT
      */
     default Optional<Value.Mutable<Living>> detonator() {
         return this.getValue(Keys.DETONATOR).map(Value::asMutable);

src/main/java/org/spongepowered/api/entity/hanging/Hanging.java

@@ -36,6 +36,7 @@ public interface Hanging extends Entity {
 
     /**
      * {@link Keys#DIRECTION}
+     *
      * @return The direction the hanging entity is facing
      */
     default Value.Mutable<Direction> hangingDirection() {

src/main/java/org/spongepowered/api/entity/living/Ageable.java

@@ -28,6 +28,8 @@ import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.util.Ticks;
 
+import java.util.Optional;
+
 /**
  * Represents an {@link Agent} that produces offspring and grows into an adult
  */
@@ -47,8 +49,26 @@ public interface Ageable extends Agent {
      *
      * @return The ticks until this entity turns into an adult
      */
-    default Value.Mutable<Ticks> babyTicks() {
-        return this.requireValue(Keys.BABY_TICKS).asMutable();
+    default Optional<Value.Mutable<Ticks>> babyTicks() {
+        return this.getValue(Keys.BABY_TICKS).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#CAN_BREED}
+     *
+     * @return Whether the entity can breed
+     */
+    default Value.Mutable<Boolean> canBreed() {
+        return this.requireValue(Keys.CAN_BREED).asMutable();
+    }
+
+    /**
+     * {@link Keys#BREEDING_COOLDOWN}
+     *
+     * @return The ticks until the entity can breed again
+     */
+    default Optional<Value.Mutable<Ticks>> breedingCooldown() {
+        return this.getValue(Keys.BREEDING_COOLDOWN).map(Value::asMutable);
     }
 
 }

src/main/java/org/spongepowered/api/entity/living/Agent.java

@@ -25,6 +25,7 @@
 package org.spongepowered.api.entity.living;
 
 import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.type.HandPreference;
 import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.entity.Entity;
 import org.spongepowered.api.entity.ai.goal.GoalExecutor;
@@ -42,6 +43,7 @@ public interface Agent extends Living, ArmorEquipable {
 
     /**
      * {@link Keys#TARGET_ENTITY}
+     *
      * @return The targeted entity
      * @see TargetGoal
      */
@@ -51,12 +53,40 @@ public interface Agent extends Living, ArmorEquipable {
 
     /**
      * {@link Keys#IS_AI_ENABLED}
-     * @return Whether ai modules are enabled on this entity or it's a "dumb" entity
+     *
+     * @return Whether AI modules are enabled on this entity or it's a "dumb" entity
      */
     default Value.Mutable<Boolean> aiEnabled() {
         return this.requireValue(Keys.IS_AI_ENABLED).asMutable();
     }
 
+    /**
+     * {@link Keys#DOMINANT_HAND}
+     *
+     * @return The dominant HandPreference of the agent
+     */
+    default Value.Mutable<HandPreference> dominantHand() {
+        return this.requireValue(Keys.DOMINANT_HAND).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_PERSISTENT}
+     *
+     * @return Whether the entity will be prevented from despawning
+     */
+    default Value.Mutable<Boolean> persistent() {
+        return this.requireValue(Keys.IS_PERSISTENT).asMutable();
+    }
+
+    /**
+     * {@link Keys#LEASH_HOLDER}
+     *
+     * @return The holder of the leashed agent
+     */
+    default Optional<Value.Mutable<Entity>> leashHolder() {
+        return this.getValue(Keys.LEASH_HOLDER).map(Value::asMutable);
+    }
+
     /**
      * Gets a {@link GoalExecutor} based on the {@link GoalExecutorType}.
      *

src/main/java/org/spongepowered/api/entity/living/ArmorStand.java

@@ -26,10 +26,10 @@ package org.spongepowered.api.entity.living;
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.MapValue;
-import org.spongepowered.api.data.value.SetValue;
 import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.item.inventory.ArmorEquipable;
 import org.spongepowered.api.item.inventory.equipment.EquipmentType;
+import org.spongepowered.math.vector.Vector3d;
 
 /**
  * Represents an Armor Stand.
@@ -57,7 +57,7 @@ public interface ArmorStand extends Living, ArmorEquipable {
     /**
      * {@link Keys#HAS_BASE_PLATE}
      *
-     * @return Whether this armorstand has a base plate or not
+     * @return Whether this armor stand has a visible base plate
      */
     default Value.Mutable<Boolean> basePlate() {
         return this.requireValue(Keys.HAS_BASE_PLATE).asMutable();
@@ -66,7 +66,7 @@ public interface ArmorStand extends Living, ArmorEquipable {
     /**
      * {@link Keys#HAS_ARMS}
      *
-     * @return Whether arms are visible or not
+     * @return Whether the arms of this armor stand are visible
      */
     default Value.Mutable<Boolean> arms() {
         return this.requireValue(Keys.HAS_ARMS).asMutable();
@@ -89,4 +89,40 @@ public interface ArmorStand extends Living, ArmorEquipable {
     default MapValue.Mutable<EquipmentType, Boolean> takingDisabled() {
         return this.requireValue(Keys.IS_TAKING_DISABLED).asMutable();
     }
+
+    /**
+     * {@link Keys#LEFT_ARM_ROTATION}
+     *
+     * @return The left arm rotation of the armor stand
+     */
+    default Value.Mutable<Vector3d> leftArmRotation() {
+        return this.requireValue(Keys.LEFT_ARM_ROTATION).asMutable();
+    }
+
+    /**
+     * {@link Keys#LEFT_LEG_ROTATION}
+     *
+     * @return The left leg rotation of the armor stand
+     */
+    default Value.Mutable<Vector3d> leftLegRotation() {
+        return this.requireValue(Keys.LEFT_LEG_ROTATION).asMutable();
+    }
+
+    /**
+     * {@link Keys#RIGHT_ARM_ROTATION}
+     *
+     * @return The right arm rotation of the armor stand
+     */
+    default Value.Mutable<Vector3d> rightArmRotation() {
+        return this.requireValue(Keys.RIGHT_ARM_ROTATION).asMutable();
+    }
+
+    /**
+     * {@link Keys#RIGHT_LEG_ROTATION}
+     *
+     * @return The right leg rotation of the armor stand
+     */
+    default Value.Mutable<Vector3d> rightLegRotation() {
+        return this.requireValue(Keys.RIGHT_LEG_ROTATION).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/Bat.java

@@ -24,9 +24,20 @@
  */
 package org.spongepowered.api.entity.living;
 
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.Value;
+
 /**
  * Represents a Bat.
  */
 public interface Bat extends Ambient, Aerial {
 
+    /**
+     * {@link Keys#IS_SLEEPING}
+     *
+     * @return Whether the bat is sleeping
+     */
+    default Value.Mutable<Boolean> sleeping() {
+        return this.requireValue(Keys.IS_SLEEPING).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/Humanoid.java

@@ -30,44 +30,19 @@ import org.spongepowered.api.entity.Tamer;
 import org.spongepowered.api.entity.living.player.Player;
 import org.spongepowered.api.entity.living.player.gamemode.GameMode;
 import org.spongepowered.api.item.inventory.ArmorEquipable;
+import org.spongepowered.api.profile.property.ProfileProperty;
 
 /**
  * Represents a human-like entity in game, such as {@link Player} or {@link Human}s.
  */
 public interface Humanoid extends Living, ArmorEquipable, Tamer {
-    /**
-     * {@link Keys#FOOD_LEVEL}
-     *
-     * @return The human's food level
-     */
-    default Value.Mutable<Integer> foodLevel() {
-        return this.requireValue(Keys.FOOD_LEVEL).asMutable();
-    }
 
     /**
-     * {@link Keys#EXHAUSTION}
+     * {@link Keys#SKIN_PROFILE_PROPERTY}
      *
-     * @return The human's exhaustion
+     * @return The skin of the humanoid
      */
-    default Value.Mutable<Double> exhaustion() {
-        return this.requireValue(Keys.EXHAUSTION).asMutable();
-    }
-
-    /**
-     * {@link Keys#SATURATION}
-     *
-     * @return The human's saturation
-     */
-    default Value.Mutable<Double> saturation() {
-        return this.requireValue(Keys.SATURATION).asMutable();
-    }
-
-    /**
-     * {@link Keys#GAME_MODE}
-     *
-     * @return The gamemode
-     */
-    default Value.Mutable<GameMode> gameMode() {
-        return this.requireValue(Keys.GAME_MODE).asMutable();
+    default Value.Mutable<ProfileProperty> skinProfile() {
+        return this.requireValue(Keys.SKIN_PROFILE_PROPERTY).asMutable();
     }
 }

src/main/java/org/spongepowered/api/entity/living/Living.java

@@ -25,6 +25,9 @@
 package org.spongepowered.api.entity.living;
 
 import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.type.BodyPart;
+import org.spongepowered.api.data.value.ListValue;
+import org.spongepowered.api.data.value.MapValue;
 import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.effect.potion.PotionEffect;
 import org.spongepowered.api.entity.Entity;
@@ -87,8 +90,8 @@ public interface Living extends AttributeHolder, Entity, TeamMember {
      *
      * @return The last attacker who attacked this entity
      */
-    default Value.Mutable<Entity> lastAttacker() {
-        return this.requireValue(Keys.LAST_ATTACKER).asMutable();
+    default Optional<Value.Mutable<Entity>> lastAttacker() {
+        return this.getValue(Keys.LAST_ATTACKER).map(Value::asMutable);
     }
 
     /**
@@ -100,49 +103,13 @@ public interface Living extends AttributeHolder, Entity, TeamMember {
         return this.requireValue(Keys.HEAD_ROTATION).asMutable();
     }
 
-    /**
-     * {@link Keys#EYE_HEIGHT}
-     *
-     * @return The height of the eyes
-     */
-    default Value<Double> eyeHeight() {
-        return this.requireValue(Keys.EYE_HEIGHT);
-    }
-
-    /**
-     * {@link Keys#EYE_POSITION}
-     *
-     * @return The position of the eyes
-     */
-    default Value<Vector3d> eyePosition() {
-        return this.requireValue(Keys.EYE_POSITION);
-    }
-
     /**
      * {@link Keys#LAST_DAMAGE_RECEIVED}
      *
      * @return The last damage received
      */
-    default Optional<Value<Double>> lastDamageReceived() {
-        return this.getValue(Keys.LAST_DAMAGE_RECEIVED);
-    }
-
-    /**
-     * {@link Keys#MAX_AIR}
-     *
-     * @return The max air supply
-     */
-    default Value.Mutable<Integer> maxAir() {
-        return this.requireValue(Keys.MAX_AIR).asMutable();
-    }
-
-    /**
-     * {@link Keys#REMAINING_AIR}
-     *
-     * @return The remaining air supply
-     */
-    default Value.Mutable<Integer> remainingAir() {
-        return this.requireValue(Keys.REMAINING_AIR).asMutable();
+    default Value.Mutable<Double> lastDamageReceived() {
+        return this.requireValue(Keys.LAST_DAMAGE_RECEIVED).asMutable();
     }
 
     /**
@@ -163,6 +130,51 @@ public interface Living extends AttributeHolder, Entity, TeamMember {
         return this.requireValue(Keys.WALKING_SPEED).asMutable();
     }
 
+    /**
+     * {@link Keys#BODY_ROTATIONS}
+     *
+     * @return The rotation of specific body parts of the living
+     */
+    default MapValue.Mutable<BodyPart, Vector3d> bodyRotations() {
+        return this.requireValue(Keys.BODY_ROTATIONS).asMutable();
+    }
+
+    /**
+     * {@link Keys#CHEST_ROTATION}
+     *
+     * @return The chest rotation of the entity
+     */
+    default Value.Mutable<Vector3d> chestRotation() {
+        return this.requireValue(Keys.CHEST_ROTATION).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_ELYTRA_FLYING}
+     *
+     * @return Whether the entity (or player) is flying with an elytra
+     */
+    default Value.Mutable<Boolean> elytraFlying() {
+        return this.requireValue(Keys.IS_ELYTRA_FLYING).asMutable();
+    }
+
+    /**
+     * {@link Keys#CAN_GRIEF}
+     *
+     * @return Whether the living entity may change blocks
+     */
+    default Optional<Value.Mutable<Boolean>> canGrief() {
+        return this.getValue(Keys.CAN_GRIEF).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#POTION_EFFECTS}
+     *
+     * @return The potion effects that are present on the living entity
+     */
+    default ListValue.Mutable<PotionEffect> potionEffects() {
+        return this.requireValue(Keys.POTION_EFFECTS).asMutable();
+    }
+
     /**
      * Converts the {@link Living}'s head rotation into a quaternion direction unit vector.
      *

src/main/java/org/spongepowered/api/entity/living/animal/Animal.java

@@ -43,30 +43,12 @@ public interface Animal extends Ageable {
     /**
      * {@link Keys#BREEDER}
      *
-     * @return The breeder's unique id
+     * @return The current breeder of the animal
      */
     default Optional<Value.Mutable<UUID>> breeder() {
         return this.getValue(Keys.BREEDER).map(Value::asMutable);
     }
 
-    /**
-     * {@link Keys#BREEDING_COOLDOWN}
-     *
-     * @return The current breeding cooldown
-     */
-    default Value.Mutable<Ticks> breedingCooldown() {
-        return this.requireValue(Keys.BREEDING_COOLDOWN).asMutable();
-    }
-
-    /**
-     * {@link Keys#CAN_BREED}
-     *
-     * @return If animal can breed
-     */
-    default Value.Mutable<Boolean> canBreed() {
-        return this.requireValue(Keys.CAN_BREED).asMutable();
-    }
-
     /**
      * Determines if the {@link ItemStack} is considered to be food by this animal.
      *

src/main/java/org/spongepowered/api/entity/living/animal/Cat.java

@@ -35,7 +35,7 @@ import java.util.Optional;
 /**
  * Represents a Cat, meow.
  */
-public interface Cat extends TameableAnimal, Sittable {
+public interface Cat extends TameableAnimal {
 
     /**
      * {@link Keys#CAT_TYPE}
@@ -108,7 +108,7 @@ public interface Cat extends TameableAnimal, Sittable {
      *
      * <p>In vanilla, a cat hisses when a {@link Phantom} is detected near it.</p>
      *
-     * @return Whether this cat is purring
+     * @return Whether this cat is hissing
      */
     default Value.Mutable<Boolean> hissing() {
         return this.requireValue(Keys.IS_HISSING).asMutable();

src/main/java/org/spongepowered/api/entity/living/animal/Fox.java

@@ -34,7 +34,7 @@ import java.util.UUID;
 /**
  * Represents a Fox.
  */
-public interface Fox extends Animal {
+public interface Fox extends Animal, Sittable {
 
     /**
      * {@link Keys#FOX_TYPE}
@@ -64,15 +64,6 @@ public interface Fox extends Animal {
         return this.getValue(Keys.SECOND_TRUSTED).map(Value::asMutable);
     }
 
-    /**
-     * {@link Keys#IS_SITTING}
-     *
-     * @return Whether this fox is sitting
-     */
-    default Value.Mutable<Boolean> sitting() {
-        return this.requireValue(Keys.IS_SITTING).asMutable();
-    }
-
     /**
      * {@link Keys#IS_FACEPLANTED}
      *

src/main/java/org/spongepowered/api/entity/living/animal/Panda.java

@@ -132,7 +132,7 @@ public interface Panda extends Animal, Sittable {
      *
      * @return Whether this panda is frightened
      */
-    default Value.Mutable<Boolean> frightened() {
-        return this.requireValue(Keys.IS_FRIGHTENED).asMutable();
+    default Value<Boolean> frightened() {
+        return this.requireValue(Keys.IS_FRIGHTENED);
     }
 }

src/main/java/org/spongepowered/api/entity/living/animal/Parrot.java

@@ -31,7 +31,7 @@ import org.spongepowered.api.data.value.Value;
 /**
  * Represents a Parrot.
  */
-public interface Parrot extends TameableAnimal, Sittable {
+public interface Parrot extends TameableAnimal {
 
     /**
      * {@link Keys#PARROT_TYPE}

src/main/java/org/spongepowered/api/entity/living/animal/Pig.java

@@ -34,6 +34,7 @@ public interface Pig extends Animal {
 
     /**
      * {@link Keys#IS_SADDLED}
+     *
      * @return Whether this pig has a saddle, and ready to be ridden
      */
     default Value.Mutable<Boolean> saddled() {

src/main/java/org/spongepowered/api/entity/living/animal/PolarBear.java

@@ -34,6 +34,7 @@ public interface PolarBear extends Animal {
 
     /**
      * {@link Keys#IS_STANDING}
+     *
      * @return Whether this polar bear is standing
      */
     default Value.Mutable<Boolean> standing() {

src/main/java/org/spongepowered/api/entity/living/animal/Rabbit.java

@@ -35,6 +35,7 @@ public interface Rabbit extends Animal {
 
     /**
      * {@link Keys#RABBIT_TYPE}
+     *
      * @return The type of rabbit
      * @see org.spongepowered.api.data.type.RabbitTypes
      */

src/main/java/org/spongepowered/api/entity/living/animal/TameableAnimal.java

@@ -30,14 +30,23 @@ import org.spongepowered.api.data.value.Value;
 import java.util.Optional;
 import java.util.UUID;
 
-public interface TameableAnimal extends Animal {
+public interface TameableAnimal extends Animal, Sittable {
 
     /**
      * {@link Keys#TAMER}
      *
-     * @return The unique id of the tamer
+     * @return The tamer of the animal
      */
     default Optional<Value.Mutable<UUID>> tamer() {
         return this.getValue(Keys.TAMER).map(Value::asMutable);
     }
+
+    /**
+     * {@link Keys#IS_TAMED}
+     *
+     * @return Whether the animal is currently tamed
+     */
+    default Value.Mutable<Boolean> tamed() {
+        return this.requireValue(Keys.IS_TAMED).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/animal/Wolf.java

@@ -31,11 +31,12 @@ import org.spongepowered.api.data.value.Value;
 /**
  * Represents a Wolf.
  */
-public interface Wolf extends TameableAnimal, Sittable {
+public interface Wolf extends TameableAnimal {
 
     /**
      * {@link Keys#IS_ANGRY}
-     * @return Whether this wolf is angry
+     *
+     * @return Whether this wolf is currently aggressive
      */
     default Value.Mutable<Boolean> angry() {
         return this.requireValue(Keys.IS_ANGRY).asMutable();

src/main/java/org/spongepowered/api/entity/living/animal/horse/Horse.java

@@ -36,6 +36,7 @@ public interface Horse extends TameableHorse {
 
     /**
      * {@link Keys#HORSE_COLOR}
+     *
      * @return The horse's color
      */
     default Value.Mutable<HorseColor> color() {
@@ -44,6 +45,7 @@ public interface Horse extends TameableHorse {
 
     /**
      * {@link Keys#HORSE_STYLE}
+     *
      * @return The horse's style
      */
     default Value.Mutable<HorseStyle> style() {

src/main/java/org/spongepowered/api/entity/living/animal/horse/HorseLike.java

@@ -24,12 +24,44 @@
  */
 package org.spongepowered.api.entity.living.animal.horse;
 
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.entity.living.animal.Animal;
 import org.spongepowered.api.item.inventory.Carrier;
 
+import java.util.Optional;
+import java.util.UUID;
+
 /**
  * An abstract representation of a Horse.
  */
 public interface HorseLike extends Animal, Carrier {
 
+    /**
+     * {@link Keys#IS_SADDLED}
+     *
+     * @return Whether the horse is saddled
+     */
+    default Value.Mutable<Boolean> saddled() {
+        return this.requireValue(Keys.IS_SADDLED).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_TAMED}
+     *
+     * @return Whether the horse is currently tamed
+     */
+    default Value.Mutable<Boolean> tamed() {
+        return this.requireValue(Keys.IS_TAMED).asMutable();
+    }
+
+    /**
+     * {@link Keys#TAMER}
+     *
+     * @return The tamer of the horse
+     */
+    default Optional<Value.Mutable<UUID>> tamer() {
+        return this.getValue(Keys.TAMER).map(Value::asMutable);
+    }
+
 }

src/main/java/org/spongepowered/api/entity/living/animal/horse/TameableHorse.java

@@ -24,8 +24,32 @@
  */
 package org.spongepowered.api.entity.living.animal.horse;
 
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.entity.living.animal.TameableAnimal;
 
+import java.util.Optional;
+import java.util.UUID;
+
 public interface TameableHorse extends HorseLike, TameableAnimal {
 
+    /**
+     * {@link Keys#TAMER}
+     *
+     * @return The tamer of the horse
+     */
+    @Override
+    default Optional<Value.Mutable<UUID>> tamer() {
+        return this.getValue(Keys.TAMER).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#IS_TAMED}
+     *
+     * @return Whether the horse is currently tamed
+     */
+    @Override
+    default Value.Mutable<Boolean> tamed() {
+        return this.requireValue(Keys.IS_TAMED).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/animal/horse/llama/Llama.java

@@ -39,6 +39,7 @@ public interface Llama extends LlamaLike, TameableHorse, PackHorse {
 
     /**
      * {@link Keys#LLAMA_TYPE}
+     *
      * @return The llama type
      * @see org.spongepowered.api.data.type.LlamaTypes
      */
@@ -48,6 +49,7 @@ public interface Llama extends LlamaLike, TameableHorse, PackHorse {
 
     /**
      * {@link Keys#STRENGTH}
+     *
      * @return The strength of this llama, determines how big of an inventory they can carry
      */
     default Value.Mutable<Integer> strength() {

src/main/java/org/spongepowered/api/entity/living/aquatic/fish/school/TropicalFish.java

@@ -34,7 +34,7 @@ public interface TropicalFish extends SchoolingFish {
     /**
      * {@link Keys#DYE_COLOR}
      *
-     * @return The base color of this tropical fish.
+     * @return The base color of this tropical fish
      */
     default Value.Mutable<DyeColor> baseColor() {
         return this.requireValue(Keys.DYE_COLOR).asMutable();
@@ -43,7 +43,7 @@ public interface TropicalFish extends SchoolingFish {
     /**
      * {@link Keys#PATTERN_COLOR}
      *
-     * @return The pattern color of this tropical fish.
+     * @return The pattern color of this tropical fish
      */
     default Value.Mutable<DyeColor> patternColor() {
         return this.requireValue(Keys.PATTERN_COLOR).asMutable();
@@ -52,7 +52,7 @@ public interface TropicalFish extends SchoolingFish {
     /**
      * {@link Keys#TROPICAL_FISH_SHAPE}
      *
-     * @return The shape of this tropical fish.
+     * @return The shape of this tropical fish
      */
     default Value.Mutable<TropicalFishShape> shape() {
         return this.requireValue(Keys.TROPICAL_FISH_SHAPE).asMutable();

src/main/java/org/spongepowered/api/entity/living/monster/Endermite.java

@@ -29,7 +29,7 @@ import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.entity.living.Monster;
 import org.spongepowered.api.util.Ticks;
 
-import java.time.Duration;
+import java.util.Optional;
 
 /**
  * Represents an Endermite.
@@ -41,7 +41,7 @@ public interface Endermite extends Monster {
      *
      * @return The despawn delay
      */
-    default Value.Mutable<Ticks> expirationDelay() {
-        return this.requireValue(Keys.DESPAWN_DELAY).asMutable();
+    default Optional<Value.Mutable<Ticks>> expirationDelay() {
+        return this.getValue(Keys.DESPAWN_DELAY).map(Value::asMutable);
     }
 }

src/main/java/org/spongepowered/api/entity/living/monster/Vex.java

@@ -34,7 +34,7 @@ public interface Vex extends Monster {
     /**
      * {@link Keys#LIFE_TICKS}
      *
-     * @return The amount of ticks till this Vex starts dying.
+     * @return The amount of ticks till this vex starts dying
      */
     default Value.Mutable<Ticks> lifeTicks() {
         return this.requireValue(Keys.LIFE_TICKS).asMutable();

src/main/java/org/spongepowered/api/entity/living/monster/boss/Boss.java

@@ -40,7 +40,7 @@ public interface Boss extends Hostile {
      *
      * @return The boss bar
      */
-    default Value.Mutable<BossBar> bossBar() {
-        return this.requireValue(Keys.BOSS_BAR).asMutable();
+    default Value<BossBar> bossBar() {
+        return this.requireValue(Keys.BOSS_BAR);
     }
 }

src/main/java/org/spongepowered/api/entity/living/monster/boss/Wither.java

@@ -39,6 +39,7 @@ public interface Wither extends Monster, Ranger, Boss, Aerial, FusedExplosive {
 
     /**
      * {@link Keys#WITHER_TARGETS}
+     *
      * @return The list of targeted entities, if available
      */
     default ListValue.Mutable<Entity> targetEntities() {

src/main/java/org/spongepowered/api/entity/living/monster/raider/Raider.java

@@ -35,6 +35,7 @@ public interface Raider extends Patroller {
 
     /**
      * {@link Keys#CAN_JOIN_RAID}
+     *
      * @return Whether this raider can join a raid
      */
     default Value.Mutable<Boolean> canJoinRaid() {
@@ -43,14 +44,16 @@ public interface Raider extends Patroller {
 
     /**
      * {@link Keys#RAID_WAVE}
+     *
      * @return The raid wave of this raider
      */
-    default Optional<Value.Immutable<RaidWave>> raidWave() {
-        return this.getValue(Keys.RAID_WAVE).map(Value::asImmutable);
+    default Optional<Value<RaidWave>> raidWave() {
+        return this.getValue(Keys.RAID_WAVE);
     }
 
     /**
      * {@link Keys#IS_CELEBRATING}
+     *
      * @return Whether this raider is celebrating
      */
     default Value.Mutable<Boolean> celebrating() {

src/main/java/org/spongepowered/api/entity/living/monster/raider/Ravager.java

@@ -70,8 +70,8 @@ public interface Ravager extends Raider {
      *
      * @return Whether this ravager is immobilized
      */
-    default Value.Mutable<Boolean> immobilized() {
-        return this.requireValue(Keys.IS_IMMOBILIZED).asMutable();
+    default Value<Boolean> immobilized() {
+        return this.requireValue(Keys.IS_IMMOBILIZED);
     }
 
     /**
@@ -84,8 +84,8 @@ public interface Ravager extends Raider {
      *
      * @return Whether this ravager is roaring
      */
-    default Value.Mutable<Boolean> roaring() {
-        return this.requireValue(Keys.IS_ROARING).asMutable();
+    default Value<Boolean> roaring() {
+        return this.requireValue(Keys.IS_ROARING);
     }
 
     /**
@@ -98,7 +98,7 @@ public interface Ravager extends Raider {
      *
      * @return Whether this ravager is stunned
      */
-    default Value.Mutable<Boolean> stunned() {
-        return this.requireValue(Keys.IS_STUNNED).asMutable();
+    default Value<Boolean> stunned() {
+        return this.requireValue(Keys.IS_STUNNED);
     }
 }

src/main/java/org/spongepowered/api/entity/living/monster/raider/illager/Pillager.java

@@ -34,8 +34,9 @@ import org.spongepowered.api.item.inventory.Carrier;
 public interface Pillager extends Illager, Carrier {
 
     /**
-     * {@link Keys#IS_CHARGING_CROSSBOW}.
-     * @return whether this pillager is charging a crossbow
+     * {@link Keys#IS_CHARGING_CROSSBOW}
+     *
+     * @return Whether this pillager is charging a crossbow
      */
     default Value.Mutable<Boolean> chargingCrossbow() {
         return this.requireValue(Keys.IS_CHARGING_CROSSBOW).asMutable();

src/main/java/org/spongepowered/api/entity/living/monster/raider/illager/Vindicator.java

@@ -35,7 +35,7 @@ public interface Vindicator extends Illager {
     /**
      * {@link Keys#IS_JOHNNY}
      *
-     * @return whether this is a johnny vindicator
+     * @return Whether this is a johnny vindicator
      */
     default Value.Mutable<Boolean> johnny() {
         return this.requireValue(Keys.IS_JOHNNY).asMutable();

src/main/java/org/spongepowered/api/entity/living/monster/raider/illager/spellcaster/Spellcaster.java

@@ -34,16 +34,18 @@ import java.util.Optional;
 public interface Spellcaster extends Illager {
 
     /**
-     * {@link Keys#CURRENT_SPELL}.
+     * {@link Keys#CURRENT_SPELL}
+     *
      * @return The current spell being casted
      * @see org.spongepowered.api.data.type.SpellTypes
      */
-    default Optional<Value.Mutable<SpellType>> currentSpell() {
-        return this.getValue(Keys.CURRENT_SPELL).map(Value::asMutable);
+    default Value.Mutable<SpellType> currentSpell() {
+        return this.requireValue(Keys.CURRENT_SPELL).asMutable();
     }
 
     /**
      * {@link Keys#CASTING_TIME}
+     *
      * @return The time to cast
      */
     default Value.Mutable<Integer> castingTime() {

src/main/java/org/spongepowered/api/entity/living/monster/spider/Spider.java

@@ -35,9 +35,10 @@ public interface Spider extends Monster {
 
     /**
      * {@link Keys#IS_CLIMBING}
-     * @return True if this spider is climbing
+     *
+     * @return Whether the spider is currently climbing
      */
-    default Value.Immutable<Boolean> climbing() {
-        return this.requireValue(Keys.IS_CLIMBING).asImmutable();
+    default Value.Mutable<Boolean> climbing() {
+        return this.requireValue(Keys.IS_CLIMBING).asMutable();
     }
 }

src/main/java/org/spongepowered/api/entity/living/monster/zombie/Zombie.java

@@ -24,11 +24,20 @@
  */
 package org.spongepowered.api.entity.living.monster.zombie;
 
-import org.spongepowered.api.entity.living.Ageable;
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.Value;
 
 /**
  * Represents a Zombie.
  */
-public interface Zombie extends ZombieLike, Ageable {
+public interface Zombie extends ZombieLike {
 
+    /**
+     * {@link Keys#IS_ADULT}
+     *
+     * @return Whether this zombie is an adult or not
+     */
+    default Value.Mutable<Boolean> adult() {
+        return this.requireValue(Keys.IS_ADULT).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/monster/zombie/ZombieVillager.java

@@ -51,4 +51,13 @@ public interface ZombieVillager extends ZombieLike {
     default Value.Mutable<ProfessionType> profession() {
         return this.requireValue(Keys.PROFESSION_TYPE).asMutable();
     }
+
+    /**
+     * {@link Keys#PROFESSION_LEVEL}
+     *
+     * @return The profession level of this zombie villager
+     */
+    default Value.Mutable<Integer> professionLevel() {
+        return this.requireValue(Keys.PROFESSION_LEVEL).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/monster/zombie/ZombifiedPiglin.java

@@ -41,4 +41,13 @@ public interface ZombifiedPiglin extends ZombieLike {
         return this.requireValue(Keys.ANGER_LEVEL).asMutable();
     }
 
+    /**
+     * {@link Keys#IS_ANGRY}
+     *
+     * @return Whether this zombified piglin is currently aggressive
+     */
+    default Value.Mutable<Boolean> angry() {
+        return this.requireValue(Keys.IS_ANGRY).asMutable();
+    }
+
 }

src/main/java/org/spongepowered/api/entity/living/player/Player.java

@@ -26,6 +26,9 @@ package org.spongepowered.api.entity.living.player;
 
 import net.kyori.adventure.identity.Identified;
 import org.spongepowered.api.block.entity.EnderChest;
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.type.HandPreference;
+import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.effect.Viewer;
 import org.spongepowered.api.entity.living.Humanoid;
 import org.spongepowered.api.item.inventory.Carrier;
@@ -61,4 +64,166 @@ public interface Player extends Humanoid, Identified, LocaleSource, Viewer, Carr
      * @return The ender chest inventory
      */
     Inventory enderChestInventory();
+
+    /**
+     * {@link Keys#AFFECTS_SPAWNING}
+     *
+     * @return Whether the player affects spawning
+     */
+    default Value.Mutable<Boolean> affectsSpawning() {
+        return this.requireValue(Keys.AFFECTS_SPAWNING).asMutable();
+    }
+
+    /**
+     * {@link Keys#CAN_FLY}
+     *
+     * @return Whether the player can fly
+     */
+    default Value.Mutable<Boolean> canFly() {
+        return this.requireValue(Keys.CAN_FLY).asMutable();
+    }
+
+    /**
+     * {@link Keys#DOMINANT_HAND}
+     *
+     * @return The dominant HandPreference of the player
+     */
+    default Value.Mutable<HandPreference> dominantHand() {
+        return this.requireValue(Keys.DOMINANT_HAND).asMutable();
+    }
+
+    /**
+     * {@link Keys#EXHAUSTION}
+     *
+     * @return The player's exhaustion
+     */
+    default Value.Mutable<Double> exhaustion() {
+        return this.requireValue(Keys.EXHAUSTION).asMutable();
+    }
+
+    /**
+     * {@link Keys#EXPERIENCE}
+     *
+     * @return The amount of experience the player has
+     */
+    default Value.Mutable<Integer> experience() {
+        return this.requireValue(Keys.EXPERIENCE).asMutable();
+    }
+
+    /**
+     * {@link Keys#EXPERIENCE_FROM_START_OF_LEVEL}
+     *
+     * @return The experience requires to advance from the current level to the next one
+     */
+    default Value<Integer> experienceFromStartToLevel() {
+        return this.requireValue(Keys.EXPERIENCE_FROM_START_OF_LEVEL).asMutable();
+    }
+
+    /**
+     * {@link Keys#EXPERIENCE_LEVEL}
+     *
+     * @return The current level the player has
+     */
+    default Value.Mutable<Integer> experienceLevel() {
+        return this.requireValue(Keys.EXPERIENCE_LEVEL).asMutable();
+    }
+
+    /**
+     * {@link Keys#EXPERIENCE_SINCE_LEVEL}
+     *
+     * @return The amount of experience the player has collected towards the next level
+     */
+    default Value.Mutable<Integer> experienceSinceLevel() {
+        return this.requireValue(Keys.EXPERIENCE_SINCE_LEVEL).asMutable();
+    }
+
+    /**
+     * {@link Keys#FLYING_SPEED}
+     *
+     * @return The speed at which the player flies
+     */
+    default Value.Mutable<Double> flyingSpeed() {
+        return this.requireValue(Keys.FLYING_SPEED).asMutable();
+    }
+
+    /**
+     * {@link Keys#FOOD_LEVEL}
+     *
+     * @return The player's food level
+     */
+    default Value.Mutable<Integer> foodLevel() {
+        return this.requireValue(Keys.FOOD_LEVEL).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_FLYING}
+     *
+     * @return Whether the entity is flying
+     */
+    default Value.Mutable<Boolean> flying() {
+        return this.requireValue(Keys.IS_FLYING).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_SLEEPING}
+     *
+     * @return Whether the player is sleeping
+     */
+    default Value<Boolean> sleeping() {
+        return this.requireValue(Keys.IS_SLEEPING);
+    }
+
+    /**
+     * {@link Keys#IS_SLEEPING_IGNORED}
+     *
+     * @return Whether this player is going to be ignored for sleeping to "reset" the day
+     */
+    default Value<Boolean> sleepingIgnored() {
+        return this.requireValue(Keys.IS_SLEEPING_IGNORED);
+    }
+
+    /**
+     * {@link Keys#MAX_EXHAUSTION}
+     *
+     * @return The maximum exhaustion of the player
+     */
+    default Value<Double> maxExhaustion() {
+        return this.requireValue(Keys.MAX_EXHAUSTION);
+    }
+
+    /**
+     * {@link Keys#MAX_FOOD_LEVEL}
+     *
+     * @return The maximum food level of the player
+     */
+    default Value<Integer> maxFoodLevel() {
+        return this.requireValue(Keys.MAX_FOOD_LEVEL);
+    }
+
+    /**
+     * {@link Keys#MAX_SATURATION}
+     *
+     * @return The maximum saturation of the player
+     */
+    default Value<Double> maxSaturation() {
+        return this.requireValue(Keys.MAX_SATURATION);
+    }
+
+    /**
+     * {@link Keys#SATURATION}
+     *
+     * @return The player's saturation
+     */
+    default Value.Mutable<Double> saturation() {
+        return this.requireValue(Keys.SATURATION).asMutable();
+    }
+
+    /**
+     * {@link Keys#SLEEP_TIMER}
+     *
+     * @return The sleep timer of the player
+     */
+    default Value.Mutable<Integer> sleepTimer() {
+        return this.requireValue(Keys.SLEEP_TIMER).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/player/User.java

@@ -27,6 +27,9 @@ package org.spongepowered.api.entity.living.player;
 import org.spongepowered.api.ResourceKey;
 import org.spongepowered.api.block.entity.EnderChest;
 import org.spongepowered.api.data.DataHolder;
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.MapValue;
+import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.entity.Entity;
 import org.spongepowered.api.entity.Tamer;
 import org.spongepowered.api.entity.living.player.server.ServerPlayer;
@@ -38,10 +41,12 @@ import org.spongepowered.api.item.inventory.entity.UserInventory;
 import org.spongepowered.api.item.inventory.type.CarriedInventory;
 import org.spongepowered.api.profile.GameProfile;
 import org.spongepowered.api.service.permission.Subject;
+import org.spongepowered.api.util.RespawnLocation;
 import org.spongepowered.api.util.annotation.DoNotStore;
 import org.spongepowered.api.world.server.ServerLocation;
 import org.spongepowered.math.vector.Vector3d;
 
+import java.time.Instant;
 import java.util.Optional;
 
 /**
@@ -147,4 +152,76 @@ public interface User extends DataHolder.Mutable, ArmorEquipable, Tamer, Subject
      * @return The ender chest inventory
      */
     Inventory enderChestInventory();
+
+    /**
+     * {@link Keys#RESPAWN_LOCATIONS}
+     *
+     * @return The spawn locations of the user may have for various worlds
+     */
+    default MapValue.Mutable<ResourceKey, RespawnLocation> respawnLocations() {
+        return this.requireValue(Keys.RESPAWN_LOCATIONS).asMutable();
+    }
+
+    /**
+     * {@link Keys#FIRST_DATE_JOINED}
+     *
+     * @return The timestamp value when this user first joined
+     */
+    default Optional<Value.Mutable<Instant>> firstJoined() {
+        return this.getValue(Keys.FIRST_DATE_JOINED).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#LAST_DATE_JOINED}
+     *
+     * @return The last timestamp value when this user has joined
+     */
+    default Optional<Value.Mutable<Instant>> lastJoined() {
+        return this.getValue(Keys.LAST_DATE_JOINED).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#INVULNERABLE}
+     *
+     * @return Whether the user is invulnerable
+     */
+    default Value.Mutable<Boolean> invulnerable() {
+        return this.requireValue(Keys.INVULNERABLE).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_INVISIBLE}
+     *
+     * @return Whether the user is invisible
+     */
+    default Value.Mutable<Boolean> invisible() {
+        return this.requireValue(Keys.IS_INVISIBLE).asMutable();
+    }
+
+    /**
+     * {@link Keys#VANISH}
+     *
+     * @return Whether the user is vanished
+     */
+    default Value.Mutable<Boolean> vanish() {
+        return this.requireValue(Keys.VANISH).asMutable();
+    }
+
+    /**
+     * {@link Keys#VANISH_IGNORES_COLLISION}
+     *
+     * @return Whether the user ignores collision with other entities
+     */
+    default Value.Mutable<Boolean> vanishIgnoresCollision() {
+        return this.requireValue(Keys.VANISH_IGNORES_COLLISION).asMutable();
+    }
+
+    /**
+     * {@link Keys#VANISH_PREVENTS_TARGETING}
+     *
+     * @return Whether the user can be targeted for attack by another entity
+     */
+    default Value.Mutable<Boolean> vanishPreventsTargeting() {
+        return this.requireValue(Keys.VANISH_PREVENTS_TARGETING).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/living/player/server/ServerPlayer.java

@@ -33,6 +33,7 @@ import org.spongepowered.api.advancement.AdvancementProgress;
 import org.spongepowered.api.advancement.AdvancementTree;
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.type.SkinPart;
+import org.spongepowered.api.data.value.MapValue;
 import org.spongepowered.api.data.value.SetValue;
 import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.entity.Entity;
@@ -41,6 +42,7 @@ import org.spongepowered.api.entity.living.player.Player;
 import org.spongepowered.api.entity.living.player.PlayerChatFormatter;
 import org.spongepowered.api.entity.living.player.User;
 import org.spongepowered.api.entity.living.player.chat.ChatVisibility;
+import org.spongepowered.api.entity.living.player.gamemode.GameMode;
 import org.spongepowered.api.entity.living.player.tab.TabList;
 import org.spongepowered.api.event.Cause;
 import org.spongepowered.api.event.message.PlayerChatEvent;
@@ -50,6 +52,7 @@ import org.spongepowered.api.network.ServerPlayerConnection;
 import org.spongepowered.api.resourcepack.ResourcePack;
 import org.spongepowered.api.scoreboard.Scoreboard;
 import org.spongepowered.api.service.permission.Subject;
+import org.spongepowered.api.statistic.Statistic;
 import org.spongepowered.api.world.border.WorldBorder;
 import org.spongepowered.api.world.server.ServerWorld;
 import org.spongepowered.plugin.PluginContainer;
@@ -170,6 +173,7 @@ public interface ServerPlayer extends Player, Subject {
 
     /**
      * {@link Keys#SKIN_PARTS}
+     *
      * @return A set of skin parts displayed
      */
     default SetValue.Mutable<SkinPart> displayedSkinParts() {
@@ -289,33 +293,6 @@ public interface ServerPlayer extends Player, Subject {
      */
     Collection<AdvancementTree> unlockedAdvancementTrees();
 
-    /**
-     * {@link Keys#FIRST_DATE_JOINED}
-     *
-     * @return The timestamp value when this player first joined
-     */
-    default Value.Mutable<Instant> firstJoined() {
-        return this.requireValue(Keys.FIRST_DATE_JOINED).asMutable();
-    }
-
-    /**
-     * {@link Keys#LAST_DATE_JOINED}
-     *
-     * @return The last timestamp value when this player has joined
-     */
-    default Value.Mutable<Instant> lastJoined() {
-        return this.requireValue(Keys.LAST_DATE_JOINED).asMutable();
-    }
-
-    /**
-     * {@link Keys#LAST_DATE_PLAYED}
-     *
-     * @return The last timestamp value when this player has played
-     */
-    default Value.Mutable<Instant> lastPlayed() {
-        return this.requireValue(Keys.LAST_DATE_PLAYED).asMutable();
-    }
-
     /**
      * {@link Keys#HAS_VIEWED_CREDITS}
      *
@@ -335,22 +312,13 @@ public interface ServerPlayer extends Player, Subject {
         return !this.firstJoined().equals(this.lastPlayed());
     }
 
-    /**
-     * {@link Keys#IS_SLEEPING_IGNORED}
-     *
-     * @return Whether this player is going to be ignored for sleeping to "reset" the day
-     */
-    default Value.Mutable<Boolean> sleepingIgnored() {
-        return this.requireValue(Keys.IS_SLEEPING_IGNORED).asMutable();
-    }
-
     /**
      * {@link Keys#SPECTATOR_TARGET}
      *
      * @return The entity this player is "spectating"
      */
-    default Optional<Value.Mutable<Entity>> spectatorTarget() {
-        return this.getValue(Keys.SPECTATOR_TARGET).map(Value::asMutable);
+    default Value.Mutable<Entity> spectatorTarget() {
+        return this.requireValue(Keys.SPECTATOR_TARGET).asMutable();
     }
 
     /**
@@ -366,4 +334,58 @@ public interface ServerPlayer extends Player, Subject {
      * @param router the chat router
      */
     void setChatFormatter(final PlayerChatFormatter router);
+
+    /**
+     * {@link Keys#GAME_MODE}
+     *
+     * @return The game mode the player has
+     */
+    default Value.Mutable<GameMode> gameMode() {
+        return this.requireValue(Keys.GAME_MODE).asMutable();
+    }
+
+    /**
+     * {@link Keys#STATISTICS}
+     *
+     * @return The statistics of the player
+     */
+    default MapValue.Mutable<Statistic, Long> statistics() {
+        return this.requireValue(Keys.STATISTICS).asMutable();
+    }
+
+    /**
+     * {@link Keys#HEALTH_SCALE}
+     *
+     * @return The value the player max-health (excluding absorption) in the GUI will scale to
+     */
+    default Optional<Value.Mutable<Double>> healthScale() {
+        return this.getValue(Keys.HEALTH_SCALE).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#FIRST_DATE_JOINED}
+     *
+     * @return The timestamp value when this player first joined
+     */
+    default Optional<Value.Mutable<Instant>> firstJoined() {
+        return this.getValue(Keys.FIRST_DATE_JOINED).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#LAST_DATE_JOINED}
+     *
+     * @return The last timestamp value when this player has joined
+     */
+    default Optional<Value.Mutable<Instant>> lastJoined() {
+        return this.getValue(Keys.LAST_DATE_JOINED).map(Value::asMutable);
+    }
+
+    /**
+     * {@link Keys#LAST_DATE_PLAYED}
+     *
+     * @return The last timestamp value when this player has played
+     */
+    default Optional<Value.Mutable<Instant>> lastPlayed() {
+        return this.getValue(Keys.LAST_DATE_PLAYED).map(Value::asMutable);
+    }
 }

src/main/java/org/spongepowered/api/entity/living/trader/Trader.java

@@ -37,7 +37,7 @@ public interface Trader extends Creature, Merchant {
      *
      * @return Whether this trader is currently trading with a player
      */
-    default Value.Immutable<Boolean> trading() {
-        return this.requireValue(Keys.IS_TRADING).asImmutable();
+    default Value<Boolean> trading() {
+        return this.requireValue(Keys.IS_TRADING);
     }
 }

src/main/java/org/spongepowered/api/entity/living/trader/Villager.java

@@ -48,6 +48,7 @@ public interface Villager extends Trader, Ageable {
 
     /**
      * {@link Keys#PROFESSION_TYPE}
+     *
      * @return The profession of this villager
      * @see ProfessionTypes
      */
@@ -63,4 +64,13 @@ public interface Villager extends Trader, Ageable {
     default Value.Mutable<Integer> professionLevel() {
         return this.requireValue(Keys.PROFESSION_LEVEL).asMutable();
     }
+
+    /**
+     * {@link Keys#EXPERIENCE}
+     *
+     * @return The experience of the villager
+     */
+    default Value.Mutable<Integer> experience() {
+        return this.requireValue(Keys.EXPERIENCE).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/projectile/DamagingProjectile.java

@@ -25,9 +25,8 @@
 package org.spongepowered.api.entity.projectile;
 
 import org.spongepowered.api.data.Keys;
-import org.spongepowered.api.data.value.MapValue;
 import org.spongepowered.api.data.value.Value;
-import org.spongepowered.api.entity.EntityType;
+import org.spongepowered.math.vector.Vector3d;
 
 /**
  * Represents a {@link Projectile} that inflicts damage.
@@ -35,20 +34,12 @@ import org.spongepowered.api.entity.EntityType;
 public interface DamagingProjectile extends Projectile {
 
     /**
-     * {@link Keys#ATTACK_DAMAGE}
+     * {@link Keys#ACCELERATION}
      *
-     * @return The attack damage
+     * @return The acceleration of the damaging projectile
      */
-    default Value.Mutable<Double> attackDamage() {
-        return this.requireValue(Keys.ATTACK_DAMAGE).asMutable();
-    }
-
-    /**
-     * {@link Keys#CUSTOM_ATTACK_DAMAGE}
-     * @return The attack damage per type
-     */
-    default MapValue.Mutable<EntityType<?>, Double> customAttackDamage() {
-        return this.requireValue(Keys.CUSTOM_ATTACK_DAMAGE).asMutable();
+    default Value.Mutable<Vector3d> acceleration() {
+        return this.requireValue(Keys.ACCELERATION).asMutable();
     }
 
 }

src/main/java/org/spongepowered/api/entity/projectile/EyeOfEnder.java

@@ -26,6 +26,7 @@ package org.spongepowered.api.entity.projectile;
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.util.Ticks;
 import org.spongepowered.math.vector.Vector3d;
 
 /**
@@ -33,6 +34,15 @@ import org.spongepowered.math.vector.Vector3d;
  */
 public interface EyeOfEnder extends Projectile {
 
+    /**
+     * {@link Keys#DESPAWN_DELAY}
+     *
+     * @return The despawn delay (in ticks) of the eye of ender
+     */
+    default Value.Mutable<Ticks> despawnDelay() {
+        return this.requireValue(Keys.DESPAWN_DELAY).asMutable();
+    }
+
     /**
      * {@link Keys#TARGET_LOCATION}
      *
@@ -42,4 +52,13 @@ public interface EyeOfEnder extends Projectile {
         return this.requireValue(Keys.TARGET_LOCATION).asMutable();
     }
 
+    /**
+     * {@link Keys#WILL_SHATTER}
+     *
+     * @return Whether the thrown eye of ender will shatter
+     */
+    default Value.Mutable<Boolean> willShatter() {
+        return this.requireValue(Keys.WILL_SHATTER).asMutable();
+    }
+
 }

src/main/java/org/spongepowered/api/entity/projectile/FishingBobber.java

@@ -38,7 +38,6 @@ public interface FishingBobber extends Projectile {
     /**
      * {@link Keys#TARGET_ENTITY}
      *
-     * @see Keys#TARGET_ENTITY
      * @return The targeted entity, if available
      */
     default Optional<Value.Mutable<Entity>> targetEntity() {

src/main/java/org/spongepowered/api/entity/projectile/Potion.java

@@ -25,7 +25,9 @@
 package org.spongepowered.api.entity.projectile;
 
 import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.ListValue;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.effect.potion.PotionEffect;
 import org.spongepowered.api.item.inventory.ItemStack;
 import org.spongepowered.api.item.inventory.ItemStackSnapshot;
 
@@ -36,10 +38,19 @@ public interface Potion extends Projectile {
 
     /**
      * {@link Keys#ITEM_STACK_SNAPSHOT}
+     *
      * @return The potion item represented by this potion
      */
     default Value.Mutable<ItemStackSnapshot> item() {
         return this.requireValue(Keys.ITEM_STACK_SNAPSHOT).asMutable();
     }
 
+    /**
+     * {@link Keys#POTION_EFFECTS}
+     *
+     * @return The potion effects of the thrown potion
+     */
+    default ListValue.Mutable<PotionEffect> effects() {
+        return this.requireValue(Keys.POTION_EFFECTS).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/projectile/arrow/Arrow.java

@@ -24,9 +24,23 @@
  */
 package org.spongepowered.api.entity.projectile.arrow;
 
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.ListValue;
+import org.spongepowered.api.effect.potion.PotionEffect;
+
+import java.util.Optional;
+
 /**
  * An arrow generally "tipped" with one or more potion effects.
  */
 public interface Arrow extends ArrowEntity {
 
+    /**
+     * {@link Keys#POTION_EFFECTS}
+     *
+     * @return The potion effects that are applied to the arrow
+     */
+    default ListValue.Mutable<PotionEffect> potionEffects() {
+        return this.requireValue(Keys.POTION_EFFECTS).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/projectile/arrow/ArrowEntity.java

@@ -26,7 +26,9 @@ package org.spongepowered.api.entity.projectile.arrow;
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.type.PickupRule;
+import org.spongepowered.api.data.value.MapValue;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.entity.EntityType;
 import org.spongepowered.api.entity.projectile.DamagingProjectile;
 
 /**
@@ -52,4 +54,31 @@ public interface ArrowEntity extends DamagingProjectile {
     default Value.Mutable<Double> knockbackStrength() {
         return this.requireValue(Keys.KNOCKBACK_STRENGTH).asMutable();
     }
+
+    /**
+     * {@link Keys#ATTACK_DAMAGE}
+     *
+     * @return The attack damage
+     */
+    default Value.Mutable<Double> attackDamage() {
+        return this.requireValue(Keys.ATTACK_DAMAGE).asMutable();
+    }
+
+    /**
+     * {@link Keys#CUSTOM_ATTACK_DAMAGE}
+     *
+     * @return The attack damage per type
+     */
+    default MapValue.Mutable<EntityType<?>, Double> customAttackDamage() {
+        return this.requireValue(Keys.CUSTOM_ATTACK_DAMAGE).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_CRITICAL_HIT}
+     *
+     * @return Whether the arrow will cause a critical hit
+     */
+    default Value.Mutable<Boolean> criticalHit() {
+        return this.requireValue(Keys.IS_CRITICAL_HIT).asMutable();
+    }
 }

src/main/java/org/spongepowered/api/entity/projectile/explosive/FireworkRocket.java

@@ -26,10 +26,15 @@ package org.spongepowered.api.entity.projectile.explosive;
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.ListValue;
+import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.data.value.Value.Mutable;
 import org.spongepowered.api.entity.explosive.fused.FusedExplosive;
 import org.spongepowered.api.entity.projectile.Projectile;
 import org.spongepowered.api.item.FireworkEffect;
 import org.spongepowered.api.item.ItemTypes;
+import org.spongepowered.api.util.Ticks;
+
+import java.util.Optional;
 
 /**
  * Represents a Firework.
@@ -45,4 +50,12 @@ public interface FireworkRocket extends Projectile, FusedExplosive {
         return this.requireValue(Keys.FIREWORK_EFFECTS).asMutable();
     }
 
+    /**
+     * {@link Keys#FIREWORK_FLIGHT_MODIFIER}
+     *
+     * @return The flight duration of the firework rocket
+     */
+    default Optional<Value.Mutable<Ticks>> flightModifier() {
+        return this.getValue(Keys.FIREWORK_FLIGHT_MODIFIER).map(Value::asMutable);
+    }
 }

src/main/java/org/spongepowered/api/entity/projectile/explosive/fireball/FireballEntity.java

@@ -34,12 +34,4 @@ import org.spongepowered.math.vector.Vector3d;
  */
 public interface FireballEntity extends DamagingProjectile {
 
-    /**
-     * {@link Keys#ACCELERATION}
-     *
-     * @return The fireball's acceleration
-     */
-    default Value.Mutable<Vector3d> acceleration() {
-        return this.requireValue(Keys.ACCELERATION).asMutable();
-    }
 }

src/main/java/org/spongepowered/api/entity/vehicle/minecart/BlockOccupiedMinecart.java

@@ -28,14 +28,25 @@ import org.spongepowered.api.block.BlockState;
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
 
+import java.util.Optional;
+
 public interface BlockOccupiedMinecart extends MinecartLike {
 
+    /**
+     * {@link Keys#MINECART_BLOCK_OFFSET}
+     *
+     * @return The represented block's offset of the minecart
+     */
+    default Value.Mutable<Integer> blockOffset() {
+        return this.requireValue(Keys.MINECART_BLOCK_OFFSET).asMutable();
+    }
+
     /**
      * {@link Keys#BLOCK_STATE}
      *
-     * @return The block state in this minecart
+     * @return The block state of the block occupied minecart
      */
-    default Value.Immutable<BlockState> block() {
-        return this.requireValue(Keys.BLOCK_STATE).asImmutable();
+    default Optional<Value.Mutable<BlockState>> block() {
+        return this.getValue(Keys.BLOCK_STATE).map(Value::asMutable);
     }
 }

src/main/java/org/spongepowered/api/entity/vehicle/minecart/CommandBlockMinecart.java

@@ -24,13 +24,65 @@
  */
 package org.spongepowered.api.entity.vehicle.minecart;
 
+import net.kyori.adventure.text.Component;
 import org.spongepowered.api.block.entity.CommandBlock;
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.service.permission.Subject;
 import org.spongepowered.api.util.locale.LocaleSource;
 
+import java.util.Optional;
+
 /**
  * Represents a {@link Minecart} with a {@link CommandBlock} inside it.
  */
 public interface CommandBlockMinecart extends BlockOccupiedMinecart, LocaleSource, Subject {
 
+    /**
+     * Gets the currently stored command.
+     *
+     * @return The command
+     */
+    default Value.Mutable<String> storedCommand() {
+        return this.requireValue(Keys.COMMAND).asMutable();
+    }
+
+    /**
+     * Gets the success count of the last executed command.
+     *
+     * <p>The success count is the number of times the most recently used
+     * command of this command block succeeded. Most commands can only succeed
+     * once per  execution, but certain commands (such as those which accept
+     * players as arguments) can succeed multiple times, and this value will be
+     * set accordingly. This success count can also be polled via a redstone
+     * comparator.</p>
+     *
+     * @return The last success count
+     */
+    default Value.Mutable<Integer> successCount() {
+        return this.requireValue(Keys.SUCCESS_COUNT).asMutable();
+    }
+
+    /**
+     * Gets whether this command block will keep track of the output from the
+     * last command it executed.
+     *
+     * @return Whether the command output is tracked
+     */
+    default Value.Mutable<Boolean> doesTrackOutput() {
+        return this.requireValue(Keys.TRACKS_OUTPUT).asMutable();
+    }
+
+    /**
+     * Gets the last command output.
+     *
+     * <p>This will only be available if {@link #doesTrackOutput()} is set to
+     * true, otherwise {@link Optional#empty()} will be returned.</p>
+     *
+     * @return The last command output, if available
+     */
+    default Optional<Value.Mutable<Component>> lastOutput() {
+        return this.getValue(Keys.LAST_COMMAND_OUTPUT).map(Value::asMutable);
+    }
+
 }

src/main/java/org/spongepowered/api/entity/vehicle/minecart/MinecartLike.java

@@ -24,11 +24,14 @@
  */
 package org.spongepowered.api.entity.vehicle.minecart;
 
+import org.spongepowered.api.block.BlockState;
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
 import org.spongepowered.api.entity.Entity;
 import org.spongepowered.math.vector.Vector3d;
 
+import java.util.Optional;
+
 /**
  * An abstract representation of a Minecart.
  */
@@ -43,21 +46,13 @@ public interface MinecartLike extends Entity {
         return this.requireValue(Keys.IS_ON_RAIL).asMutable();
     }
 
-    /**
-     * {@link Keys#SWIFTNESS}
-     *
-     * @return The current swiftness of the minecart
-     */
-    default Value.Mutable<Double> swiftness() {
-        return this.requireValue(Keys.SWIFTNESS).asMutable();
-    }
-
     /**
      * {@link Keys#POTENTIAL_MAX_SPEED}
      *
-     * <p>This differs from {@link Minecart#swiftness()} in that its value is
+     * <p>This differs from {@link Entity#swiftness()} in that its value is
      * affected by the block/rail beneath the cart. However, it is still
      * impacted and limited by the cart's swiftness.</p>
+     *
      * @return The potential maximum speed
      */
     default Value.Mutable<Double> potentialMaxSpeed() {

src/main/java/org/spongepowered/api/entity/weather/LightningBolt.java

@@ -24,9 +24,30 @@
  */
 package org.spongepowered.api.entity.weather;
 
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.util.Ticks;
+
 /**
  * Represents a Lighting Bolt.
  */
 public interface LightningBolt extends WeatherEffect {
 
+    /**
+     * {@link Keys#DESPAWN_DELAY}
+     *
+     * @return The despawn delay (in ticks) of the lightning bolt
+     */
+    default Value.Mutable<Ticks> despawnDelay() {
+        return this.requireValue(Keys.DESPAWN_DELAY).asMutable();
+    }
+
+    /**
+     * {@link Keys#IS_EFFECT_ONLY}
+     *
+     * @return Whether the lightning bolt is harmful to other entities
+     */
+    default Value<Boolean> effectOnly() {
+        return this.requireValue(Keys.IS_EFFECT_ONLY);
+    }
 }

src/main/java/org/spongepowered/api/item/merchant/Merchant.java

@@ -55,7 +55,12 @@ public interface Merchant extends DataHolder.Mutable, Carrier, Locatable {
      */
     void setCustomer(@Nullable Humanoid humanoid);
 
-    default ListValue<TradeOffer> tradeOffers() {
+    /**
+     * {@link Keys#TRADE_OFFERS}
+     *
+     * @return The trade offers offered by the merchant
+     */
+    default ListValue.Mutable<TradeOffer> tradeOffers() {
         return this.requireValue(Keys.TRADE_OFFERS).asMutable();
     }