Way too slow

At first I thought this game was really fun. Something simple to kill some time. But once you run out of energy, there is no way to continue without doing one of two things- leaving the game running for hours or spending at least $4.99 for an in game purchase. Make energy a little easier to gain, and then maybe I will actually spend money on some of the other in-game purchases.

ridiculous14 about Zombies Ate My Friends