Hmm, it seems to be less intuitive than the rest, perhaps?
if properly implemented, it would be moreso, actually.
I can't say I can put my finger on exactly how this one works.
Basically, if you press down, then it squishes from front to back; grey tiles that are in front of green tiles block them, but green tiles in front of grey tiles will replace them. When you unsquish, you get brought to the lowestmost green square. Same for other directions. It's sort of like a rotation, with only the frontmost square counting, I think, and if I had an animation that illustrated that when you pressed the squish button, then everything would suddenly become clear...
(and yeah, it has the same laggy control setup as before).
What's with the name, eh?
I've had marx on my mind recently, to be sure, but it's essentially a codename with no relationship to the prototype itself...