OptiLithium Reforged

Lithium is a general-purpose optimization mod for Minecraft which works to improve a number of systems (game physics, mob AI, block ticking, etc) without changing any behavior. It works on both the client and server, and can be installed on servers without requiring clients to also have the mod.

OptiFine and Lithium refuse to start together: Lithium declares “breaks”: {“optifabric”: “*”} in its own fabric.mod.json, and Fabric Loader matches that by mod id. This repackage removes that one entry, so both load. No class file is changed — Lithium’s own id, name, version and licence are untouched. Bring your own OptiFine jar.