Spleef-OG runs multiple concurrent arenas in WorldGuard regions inside ordinary worlds. It never creates, copies, or unloads a world; an arena is just a region of a world you already have.

Gameplay

Classic Spleef gives each player a shovel. Broken snow floors award snowballs, and thrown snowballs break configured floor blocks.
Bow Spleef gives each player an infinity bow and one arrow. Arrow impacts break configured floor blocks.
An arena starts a 20-second countdown as soon as at least two players are waiting. The countdown pauses if fewer than two remain.
The last surviving player wins. Matches draw when the configured time limit expires.
Waiting players, active players, and spectators have their inventory, location, gamemode, health, experience, effects, flight state, and scoreboard restored when they leave.
A trident still in flight when a player joins is taken out of the world and handed back with the rest of their inventory. Without this it is simply lost: the player is teleported away from it, Loyalty cannot follow them into the arena, and the entity despawns while the match runs. The trident is moved rather than copied, so one already picked up or returned by Loyalty yields nothing.
An ender pearl still in flight when a player joins is removed, so it cannot land mid-match and fire a teleport.
Recovery snapshots survive plugin or server restarts, including any returned trident.
Players cannot walk, teleport, or command their way out of an arena while holding a Spleef kit, and players with no session cannot teleport into one. See Protection below.

Spleef statistics are stored in plugins/Spleef-OG/stats.yml. Every data file (arenas.yml, stats.yml, recovery.yml) is written through a temporary file and moved into place, and a file that cannot be parsed is moved aside under a .corrupt-<timestamp> name rather than overwritten. Use /spleef stats [player] to see wins, losses, ties, and games played.

Requirements

Java 17+ at runtime
Purpur / Paper 1.19.4
WorldGuard 7

Every dependency resolves from a public Maven repository; nothing needs to be vendored to build this. The Gradle toolchain is pinned to a GraalVM 17 JDK, so building needs one installed (or the TrueOG bootstrap that provides it).

Optional, integrated when present: EternalCombat-OG, BattleTracker, GameModeInventories-OG, Scoreboard-OG, Spawn-OG, PlayerBounties-OG, and Essentials. See Integrations below.

Configuration

config.yml defaults to one allowed world:

world-whitelist:
  - world

It also controls the minimum player count, 20-second waiting period, match time limit, victory delay, tools, and scoreboard. Some values have floors that are applied silently: match.minimum-players is never below 2, match.time-limit-seconds never below 30, and performance.reset-blocks-per-tick never below 256.

Arena worlds do not need to be loaded when Spleef enables. An arena whose world is loaded later by a world manager becomes usable as soon as the world exists, and an arena whose world is unloaded is simply unavailable until it returns.

Values may be written in MiniMessage or in legacy & colour codes; both are accepted in the same string.

Protection

protection:
  block-teleports: true
  block-all-commands: false
  whitelisted-commands: [msg, r, reply, tell, whisper, list]
  blacklisted-commands: [spawn, home, back, tp, gamemode, ...]

block-teleports cancels any teleport whose destination is outside the arena region. Destinations inside the region are always allowed, so the plugin's own teleports need no special case.
The reverse is also enforced: a player with no Spleef session is turned away from teleports that land inside any enabled arena, such as /tpa to someone in a match. Every other guard keys on having a session, so without this an outsider arrives completely unprotected. spleef.admin and spleef.bypass.teleport are exempt, as are the plugin's own restore teleports.
Command matching resolves namespaced spellings and registered aliases, so home also covers essentials:home. Multi-word entries such as union home match the start of what the player typed.
/spleef is always permitted, so a player can never be trapped in an arena.
spleef.bypass.teleport and spleef.bypass.commands exempt a player. Both default to nobody.

Performance

performance:
  reset-blocks-per-tick: 8192

Floor restoration is capped per tick. An arena larger than the budget finishes over the following ticks rather than stalling the server. Restoration skips blocks that already match, clamps to the world's build limits, and loads the chunks it needs deliberately instead of incidentally.

Arena Setup

The region must deny building to ordinary players. Spleef re-allows only the block breaks a match needs; the floor between matches, and everything in the arena that is not a layer, is protected by WorldGuard alone. A region created with /rg define and no members does this by default. Spleef logs a warning if the region's flags say otherwise.

Create a WorldGuard region and allow Spleef in it:

/rg define spleef_classic
/rg flag spleef_classic allow-spleef allow

Stand inside the region, then configure the arena:

/spleef create classic classic
/spleef setwait classic
/spleef setspectator classic
/spleef addspawn classic
/spleef addspawn classic
/spleef layer add classic
/spleef layer material classic minecraft:snow_block
/spleef deathregion classic
/spleef info classic

layer add and deathregion ask for two block clicks with the main hand; left or right click both work. After the second corner of a layer, run /spleef layer material <arena> <block data> to finish it; the prompt is clickable and the block data argument tab-completes. /spleef info lists whatever setup steps are still outstanding. Arena definitions are stored in plugins/Spleef-OG/arenas.yml.

Use bow instead of classic in the create or mode command for Bow Spleef.

Player Commands

Command	Description
`/spleef arenas`	Show currently available arenas and their join commands.
`/spleef join`	Show currently available arenas.
`/spleef join <arena>`	Join a named arena.
`/spleef leave`	Leave the current arena or spectator session.
`/spleef spectate <arena>`	Spectate an arena. `spec` is accepted as an alias.
`/spleef stats [player]`	Show Spleef statistics.
`/spleef help`	Show the command list.

Administration

Command	Description
`/spleef create <name> [classic\|bow]`	Bind a new arena to the smallest WorldGuard region containing you.
`/spleef delete <arena>`	Delete an inactive arena.
`/spleef setwait <arena>`	Set its waiting spawn.
`/spleef setspectator <arena>`	Set its spectator spawn.
`/spleef addspawn <arena>`	Add a player spawn.
`/spleef clearspawns <arena>`	Remove all player spawns.
`/spleef layer add <arena>`	Click two corners to select a floor layer.
`/spleef layer material <arena> <block data>`	Finish the selected layer.
`/spleef layer <remove\|list\|clear> <arena> [index]`	Manage existing layers.
`/spleef deathregion <arena>`	Select the elimination volume.
`/spleef cancel`	Abandon a pending layer or death-region selection.
`/spleef mode <arena> <classic\|bow>`	Change game mode.
`/spleef enable <arena>`	Enable an arena.
`/spleef disable <arena>`	Disable an inactive arena.
`/spleef info <arena>`	Show setup and runtime state.
`/spleef reload`	Reload `config.yml`, and `arenas.yml` too when no arena has anyone in it. While any arena is in use only `config.yml` is reloaded and the busy arenas are listed.

Player permissions are spleef.play, spleef.spectate, and spleef.stats. Administration uses spleef.admin. The bypasses spleef.bypass.teleport and spleef.bypass.commands default to nobody.

Integrations

Combat tags prevent joining. EternalCombat-OG is asked first and BattleTracker second, because BattleTracker's combat-log feature is commonly disabled where both are installed and would otherwise answer "not in combat" for everyone. Duels and Spleef activity are excluded from BattleTracker's SMP statistics.
GameModeInventories-OG has gamemodeinventories.use and .death suspended while Spleef owns a player's inventory, and .spectator granted so eliminated players can actually become spectators. Because it vetoes adventure mode in worlds on its restrict_adventure_worlds list, Spleef clears that veto for its own players; without this the plugin cannot put anyone into adventure or spectator mode at all.
Scoreboard-OG is asked to close its sidebar on entry and reopen it a tick after a player is restored. It asserts its sidebar only once and has no re-assert loop, so without this its sidebar stays blank after a match.
Spawn-OG's respawn handling is overridden inside an arena by listening at a higher priority, and recovery after a relog is deferred a few ticks so its asynchronous login teleport cannot land on top of the restore.
Essentials has its recorded back location repointed at the player's pre-Spleef spot when they are restored. Otherwise the restore teleport leaves /back aimed at the arena, which the teleport guard then refuses.
HorseTp-OG and PetTeleport-OG suppress teleports while SpleefAPI.isInSpleef is true.
PlayerBounties-OG claims and placements involving Spleef players are cancelled.

API

import net.trueog.spleefog.api.SpleefAPI;

if (SpleefAPI.isInSpleef(player)) {
    // Player is waiting, playing, or spectating.
}

SpleefJoinEvent and SpleefLeaveEvent are available in the same package.

Building

./gradlew build

The jar is written to build/libs.