It's a bit odd that the slow-moving character has the higher rate of fire and the lower damage of the two classes. Note that that I say "odd", not "bad". 5/5 for sheer entertainment value.
To begin with, there are some annoying issues, like the lack of friction and random collapses caused by wobbling blocks. Also, the blocks seem to come in groups - I always get three Z-shaped pieces, then two L's, then three blocks, etc. In addition, it is unbelievably annoying to have your carefully constructed tower collapse because a falling piece brushes up against an off-center part of the tower, becomes uncontrollable, falls, and takes half the tower with it. There needs to be a delay between when the block touches the tower and when you lose control of it, like in Tetris. On the other hand, this game has a great concept behind it (unlike most of the "games" on this site) and has perfectly captured that "one-more-time" feeling that can lead to hour-long playing sessions. Overall, I give it a 3/5.
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 ":the game:")
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