Removing Minecraft RNG in the most brutal way possible

Patches every call to JavaRandom to be deterministic.

Used as an optional dependency for TASmod and in Tool-Assisted Speedrunning to make the game deterministic.

Can be used to change RNG seeds individually, for scientific purposes.

Commands

/killtherng <RNGName> Read the current RNG seed of that value and how many times it has been called
/killtherng <RNGName> <RNGSeed> Set the seed of that value.
/seedingmode Change how and if the RNG value should change. Can be on every tick and more.

Multiplayer

Does work on multiplayer, however a server side installation is required

Caution!

Some unintended side effects may happen when using this in your world. Use with care and play on a backup!