I wrote my own high speed compression format: https://github.com/cvghivebrain/HiveRLE Compression ratios aren't great, but they generally seem to be slightly better than SNKRLE. For data with lots of repeating bytes it'll actually compress better than Kosinski. I'm using it to compress level layouts. The HiveDec (to RAM) subroutine can be found in the asm folder. Decompressing to VRAM is untested and probably needs rewriting.