Mnemonics

Fossils, aggregators and jars make up the storage system. A fossil is found as an ore deposit and can hold experience as a device placed adjacent to a source. Aggregators are crafted from fossil copper bricks and can be interacted with to extract experience losslessly, one level at a time. Standing near a fossil and absorbing experience or breaking a block returns the points without loss.

Jars are portable and craftable, and they stack to 16. A single jar holds a fixed amount of points, and a double chest of jars can store far more. A dedicated experience bottle item is included for players who want to carry XP in a simpler form. Experience orbs and bottles can be used for mending or enchanting directly from storage.

Mnemonics is a Fabric mod that works with mods which rebalance the experience curve, and the author notes that devices store points rather than levels, so the tuning of a curve, such as the 1395 points needed for level 30, is respected. Redstone is supported: comparators read stored amounts, and dispensers, pistons and displacing actions can move jars and fossils. The mod adds 3 blocks and 1 item in total. It is published for 1.16 – 1.21.1 across 12 release versions, with 1.5.2 for 1.21.1 as the latest Fabric file.