The Anti Td tower defense game works differently from most traditional Tower Defense strategies. You are in charge of sending the creeps out onto the ground and ensuring they reach the gate. The cpus task is to build turrets in order to stop the creeps you send out for reaching their goal of the exit. You can send out stronger creeps and alter the road they take from the pathway to the gate. In order to unlock the next grade you need to make sure that the required amount of creeps make it to the door.