Average shooter defense game.
click to shoot, medium draw distance. Overall unmemorable, but inoffensive.
We shouldn't need to know that a wave has ended, and have to click to advance the game. Slows the whole thing down a lot. The zombies are too far away to make them look like anything other than generic. The pacing and spacing of the zombies keeps them from feeling threatening or make any of them a real priority.
Gun damage seems a bit lack luster, at least on the cannon/RPG. It lacks a AOE and does only as much as the sniper, but is slower and makes it less useful.
Also, no progression system makes level 1 and level 51 feel the same, except for the number of things on screen.