@neauoire That's true :)

https://wiki.xxiivv.com/site/formats.html right? I've read through the docs before, just haven't written something in uxn myself yet.

I don't see a reason why LZ77 based compression wouldn't likely help here. There's a reason LZSS-variants are common on NES and GB/GBA/DS devices https://www.nesdev.org/wiki/Tile_compression#LZSS