Z.A.R. was released on Steam by Night Dive Studios.

it doesn't require a MMX processor but it ships with a MMX enabled executable. Everytime I try to use the pentium_mmx core in Daum (the only one I can even run because the latest build just complains about a library being ELF64) anything that tries to use a MMX instruction locks up Daum, and I'm too lazy to setup a VM.

Anybody that owns this game hardcopy or Steam could give me any clues as to what the MMX executable even has over the non MMX? Only thing I can think of is the terrain might be a little less glitchy and render faster.