This game feels very limited due to the lack of variation and creativity between towers. Also, the gameplay tends to be very lame. Instead of having zombies destroy barricades, have them try to vault over them. Also, defensive towers shouldnt be deactivated by zombies. The upgrades for everything cost too much compared to what you can reasonably earn. Also, the difficulty goes from easily killed zombies in large hordes to massive packs of zombies that have too much health to be killed.
-E135- about SAS: Zombie Assault TD