Artifactory

Items are bonded through the Attuning mechanic. Once an item is attuned to a player, only that player can use it, and holding it while bonded to someone else has harmful effects. Each bond grows with the player and adds gains such as the unbreakable attribute or soulbound behavior, which keeps an item through death. Attuned items are also protected from despawning and from destruction by the environment. Limited attunement slots and restrictions, for example requiring an item to be attuned before it can be used, shape which gear a player chooses to invest in.

The attunement system is driven entirely by data. The default vanilla datapack defines three attunement levels for a diamond sword, with level 1 making the item invulnerable and immune to despawning and environmental effects, level 2 adding 25% attack speed and unbreakable, and level 3 adding 40% more attack speed and soulbound behavior. Modpack makers can change nearly every value, and the mod adds Curios compatibility. It is distributed for Forge and NeoForge on 1.20.1 and 1.21.1, and the client and server both need it. The code is released under the Creative Commons Attribution 4.0 license, and the source is public.