What is DupeBull?
DupeBull is a plugin for anarchy servers to reintroduce dupe glitches in the latest version of paperspigot.
It is no longer maintained and no support will be given, use at your own risk!
It has no configuration file and is extremely barebones, if you want to improve it feel free to clone or fork the project.
Usage (for players)
Get on a chested horse with items inside the chest and on half a heart. Get right next to a nether portal and run /dupebull or /db. If fulfilled, the chested horse will be killed and its inventory will be dropped twice.
Github (Source): https://github.com/Vonr/DupeBull
Prebuilt Jar: https://drive.google.com/file/d/1npDYXXxWOw4AIPR4O8_ID5ZmT1EhyGyf/view?usp=sharing