I still have TIS-100 under the Languages skill section of my resume as an Easter Egg. I haven't played many of Zach's recent games, but SpaceChem, Opus Magnum, and TIS-100 were some of the best puzzle games ever made to me.
TIS-100 and Shenzen had that fun little bit of hacking using the docs. Or just fiddling with it and finding that one instruction that had enough of a side effect where it could let you shave off two other instructions. Where you could get that really fun rush of removing 1 cycle from something. It is a skill I do not get to use much anymore as most things are fairly cookie cutter.
As as assembly language enthusiast, TIS-100 is easily my #1 Zachtronics game.
The closet contender would be... CoreWar. Seems like their implementations are rarely updated these days.
Robocode is also cool, but you code in Java instead of assembly, anyway.
