Zombies are the main enemy in the Zombotron series of games. Zombies are typical undead humans that eat human flesh and are reasonably easy to kill. Zombies attack all the other creatures in the game, making it easier because the zombies will kill most of the other enemies. Zombies becomes an easier enemy in Zombotron 2 because you can perform headshots that kill them instantly, and the sword can kill a Zombie in one swipe. Zombies lack strength on their own, but the player must be careful when fighting larger groups, as their size offsets their lack of strength.
The green zombies are the most commonly found on Zombotron. Some appear in different colors (green, wearing pink pants, orange, wearing cyan pants, and blue, wearing brown pants). They can easily be killed by a headshot or a knife.
Helmet zombies are zombies that wear metal welding helmets. These zombies are harder to kill because you have to shoot through the helmet to get to the head and are not prone to headshots unless the helmet is shot off. They can also be instantly killed by a knife or Mossberg by shooting on the torso. However, they are not killed by elevators. Blue zombies wear bronze helmets, orange zombies wear silver helmets and green zombies wear gold helmets.
Headless zombies are zombies that don't have heads, so cannot be killed via a headshot. They carry bombs and once they are killed, the bomb is activated and it eventually explodes. The bomb can be shot while it is activated and triggers the explosion earlier, or it can be left to roll until it explodes on its own. The bomb also activates if the player gets near to the Zombie. Their only method of attack is to walk into the player, where they will explode in a kamikaze-style attack, they will occasionally blow up when there is something in their way.
Giant Zombies only appear in Zombotron 2 and Zombotron 2: Time Machine. They are always green. They are much harder to kill because they are bigger than normal zombies. They can kill you in one or two blows however a desert eagle is powerful enough to kill them with about 1-2 magazines and is prone to headshots. A strategy to kill them without being hurt (although slow) is to guide them into a trench, then stay just out of their range and repeatedly whack them on the head or shoot them in the head.