The physics make this game. As far as I can tell they are flawless. As far as lag, get a better computer. As far as keys locking up - it is an aspect of the game. Some games when you are holding left and then press right the right takes precedence. This game is not that way. Simply get used to the feel of the controls and you should have no problems. Finished all levels, none are unbeatable; have fun!
My favorite on Kongregate, most definitely! Each day I hope and pray for a sequel with more variation in the levels - still a very well made TD with a sweet and inventive upgrading system and I love the gembombs. 5/5!
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