Helium(Formerly Hydrogen Reforged) is an Unofficial port of CaffeineMC's "Hydrogen" Mod, Ported from Fabric to Forge.

(Yes this has been uploaded before)


Helium is a free and open-source mod designed to reduce the game's memory requirements by implementing more memory-efficient data structures and logic. It's primarily designed for more heavily modded scenarios, but can offer (small) improvements even in lightly modded or vanilla scenarios.


The mod works on both the client and server, and doesn't require the mod to be installed on both sides. However, the benefits of running Hydrogen on the server are pretty small as of the moment.



  •  Implements more compact data structures for block states and properties, reducing memory usage significantly when using mods that add lots of complex blocks
  • De-duplicates block model geometry, saving memory on the client when multi-part block models are used
  • Fixes a few leaks in chunk loading code that results in the NBT data on disk being kept in memory after a chunk has loaded
  • Simplifies and flattens block model predicates to reduce unnecessary chaining


Mod Compatibility

Helium does not play nice with create as of now. I will need to look into this in the future.


For now, this mod will be maintained in 1.16.5 and 1.18+.