Tower defense hasn't had its day just yet, judging not only by the large percentage of games on the App Store that hail from the genre, but also this insane-looking monstrosity from developer MCRO. Eight-player online co-op and an additional dimension are the game's selling points, as is an 8-bit soundtrack, which may or may not pillage the sanctity of your eardrums.
The game's objective is to make use of nine different turret types to destroy waves of 3D objects that barely classify as spheres. Doing this by yourself already sounds like a challenge, but with seven others?
I can't even begin to fathom how playable Terrorhedron is -- I had enough trouble mastering the two dimensions of geoDefense on iPhone. It definitely gets points for the name and attempting to add more depth to the traditional tower defense formula by offering programmable turrets (probably not to the same complexity as Carnage Heart, but then, what could ever match Carnage Heart?), but without a demo it's hard to gauge how fun it is all blended together.
Clips. Games are always easier to understand with clips. Hence the one below. The backing music does improve once you get past its head-exploding intro, but only just.