Phantom Storage

The summoned chest floats and drifts 2 to 5 blocks around its owner, trailing and bobbing as the player moves, then settles beside a foot when they stop. It emits light at level 7, like a redstone torch, and with LambDynamicLights installed it lights the surroundings at that level. Only the owner can open or move it, and each player has one chest at a time.

Storage held in the chest persists across death, logging out and moving between dimensions, whereas the summon itself is dismissed automatically when the player logs out or changes dimension, and the Phantom Charm brings it back. Contents are a 12 by 9 personal inventory, and a trash-can button destroys whatever it holds. Items left open in the GUI return to the player's inventory when it closes. The mod runs on NeoForge for 1.21.1 and is needed on client and server, so both the server and every player must install it.

Upgrading from the 1.x chest is handled in steps. Its contents move to the v2 storage automatically the first time a player logs in, but anything that does not fit, which for a 54-slot chest means nothing since v2 has 108 slots, stays where it was. Filter and refill templates are not carried over, and wrench anchor links to blocks must be rebuilt. Removed mods leave their items in place until the chest is opened again.