Crawler Zombie

"These must have been the failed experiments Maxis mentioned."

- Doctor Richtofen

Crawler Zombies (called Creepy Crawlers in Dead Ops Arcade) are a special type of Zombie featured in Call of Duty: Black Ops. According to Dr. Richtofen, they are failed experiments. Crawler zombies are not to be confused with "crawlers", a common name for zombies that have had their legs shot/blown off.

Overview
"That thing could not ever have been human!"

- Takeo Masaki when killing a Crawler zombie.

Crawler zombies are skinny zombies who run around on all four limbs. Based on their appearance, Crawler zombies seem to be mutated much more than regular zombies. Richtofen gives an explanation that they were a failed experiment of some sort. They have a slimy, greenish gray shade of skin and appear to be wearing only either a loin cloth or shorts. They emit a very distinct trail of green gas that makes them quite noticeable among the horde. Furthermore, they have not retained their human facial features, and instead an over-sized angler fish-like mouth is the only prominent feature on the face.

Crawler zombies can be quite subversive and hard to see as they stay close to the floor. When killed, they will flip onto their backs, curl up (similar to a spider), and emit a cloud of green toxic gas that is dangerous to the player as vision becomes blurred, similar to the effects of Nova Gas in multiplayer (though looks and acts like Tabun Gas from World at War multiplayer). They will not, however, release the cloud of gas if the final blow dealt to them is a knife attack, Ray Gun, Thunder Gun, Winter's Fury, Ballistic Knife, explosives, if standing too close to a Teleporter, or if the player kills them while they crawl down the walls. The player will also take a small amount of damage if they stay near the gas for too long.

In Dead Ops Arcade, creepy crawlers appear at round 13 in the challenge round called "Creepy Crawlers." Crawlers zombies do not appear in Ascension nor do they appear in Call of the Dead or Shangri-La but they are seen in the Rezurrection Preview, hinting that Crawler Zombies will return in Moon.

When a crawler zombie explodes all zombies in radius of the explosion will die instantly which can be helpful in clearing large groups in the later levels.

Trivia

 * There are several backgrounds featuring Crawler zombies can be purchased for use in the playercard in multiplayer.
 * In the Call of Duty: Black Ops official game guide, they are called Gas Zombies.
 * Oddly enough, sometimes after a headshot is executed, the gas zombie can produce sounds for a couple of seconds. (Confirmed on Xbox 360)
 * In the campaign mission WMD, an x-ray image of a Crawler zombie could be in the room which the player is then locked in by Steiner. If the player goes to the wall opposite to the door that player entered through, there are x-ray photos on a desk. One of these photos could be from a Crawler zombie, since the skull only has a large mouth similar to these zombies.
 * Crawler zombies can get their legs blown off and crawl in the same fashion as normal zombies.