Use towers to build a labyrinth from entrance to exit. Each tower can be upgraded 4 times. With each wave, enemies will become stronger, so use money you earned to upgrade reasonably.
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.
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.
