Only criticism would be that it needs hot keys, Numbers for towers and letters for mosters would be a good way to go. Not totally my kind of game but I'll give it a good rating as it is a good game for the type, excluding hot key issue.
Jus add, I also have had a problem once or twice trying to load the game where the play doesnt pop up, I have to refresh my page, and it will pop up without loading, if this is my problem and not the games I do not know but I thought I would mention it, cause it has happened on other sites as well
You should be able to combine the gems in the towers, and you should be able to combine them without using all of your mana, I always run out making them and cannot combine new ones
I think the only real criticism for this game is to make a ff button to press instead of hold, and as indianhottie said to make it different speeds not just a single one. It would keep the game more interesting instead of having to wait for each wave to finish. Other then that excellent game
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