Bit obviously noticed that Tetris was instrumental in the Game Boy's success, and realised that they too needed a killer app to compete. So the Gamate's answer to Tetris was... a Tetris clone. I think they missed the point a bit, but hey.
See, the title screen has a European instead of a Russian castle on it. That makes it original.
There's only one game mode, which seems to be somewhat of an endless mode, although there's more of a tangible break between levels rather than it just getting a bit faster. I have no idea if it has cutscenes, or even if the levels continue after 9, for reasons that will become apparent later.
Much like Tetris, Cube-Up has three selectable BGMs - they're all decent enough, certainly much better than the out of tune knockoff of the Mario Land theme featured in Block Buster (the Supervision's Tetris clone). None of them are a patch on Korobeiniki, though.
Looks very GB Tetris-ish, and indeed it is. Even the block designs and the font are pretty similar. It has the addition of lives, which allow you to continue three times before a game over, but they really don't make a difference to anything. What does make a difference, though, is one particular gameplay oversight.
Basically, when a block hits either the top of another block or the bottom of the shaft (teehee), in most official versions of Tetris you have some leeway to move the block around before it locks into place. In Cube-Up, you don't. This, coupled with the inexplicable lack of an anticlockwise rotation button, means it's incredibly easy to get blocks stuck in places you didn't mean to stick them, making the game way more frustrating than it should be and removing a whole strategic element (ever let a block drop to the lowest level before moving it left or right to slot it into place? yeah, you can't do that). So I suppose what I'm saying is, if you code an otherwise competent Tetris clone, don't bloody forget about that.
(click for hi-res versions)
additional pics: english box with french/german stickers - front / back (from some auction)