I agree with video game mania, 9 is almost impossible, i almost didnt make it, 10 is real easy, and 11 is kind of hard, just dont let the teacher see you whenshe tells the teens to go back to their seats.
easy, at the last 10 waves just summon satan and have 2 turrets at the land and air, buy another heart, and use the meatl blocks to protect you r tower and turrets.(the ones that cost 60$)
I go through 20 horrible levels of the game, trying to survive the bosses and zombies, thhen at the end i kill my teammate and while were chattin i look at the window and "what the fuk!!?!?!?" I mean, all the bosses came out!!! Overall, 3/5 stars bcuz 1- u need to refresh and 2- u gotta kill ur friends to fight the last battle. :(