ThunderBucket

A lightweight Paper plugin that lets players throw empty, water and lava buckets like snowballs by firing a bow or crossbow while holding the bucket in the off-hand.

Behaviour

Bucket	On impact
Empty bucket	Drops as an item
Water bucket	Places a water source + drops an empty bucket
Lava bucket	Places a lava source + drops an empty bucket

Main hand: bow or crossbow
Off-hand: empty / water / lava bucket
Firing the bow/crossbow consumes the off-hand bucket and launches it (no arrow appears)
Looks and flies like a thrown item (uses Snowball physics with the correct bucket visual)
Consumes one bucket from the stack in Survival / Adventure
Creative mode does not consume the item
Never breaks blocks when placing liquid (only replaces air / replaceable blocks)
Empty bucket drop is invulnerable so lava cannot destroy it

Building

mvn clean package

The resulting jar will be at target/ThunderBucket-1.0.0.jar.

Installation

Drop the jar into your server’s plugins folder
Restart the server (or load it with a plugin manager)
Put a bucket in the off-hand, hold a bow or crossbow in the main hand, and fire

Notes

Currently hard-coded (no config.yml yet). Ask if you want cooldowns, permissions, particle trails, sound volume, max throw distance, etc.
Compatible with pure Paper and hybrid servers that expose the Paper/Bukkit API (including Youer).