The forces of Darkness have bursted into our world. They walk along the land destroying the kingdoms one by one. But we can stop them! The way of the evil forces passes through a narrow canyon that is perfectly adapted for our ambush attack.
Build towers and survive through 51 hardcore waves of aliens that heal themselves, haste other enemies, split into more enemies and freeze your towers.
Monsters must protect San Francisco or even the world from these evil aliens. Place your monsters around the map to defeat the incoming waves of aliens.