The Walker's appearance is considered to be quite monstrous and grotesque, resembling the Blair-Thing's own appearance. They possess two large claws on both arms and large spider-like legs, it also seems to have a human torso attached to its' body believed to be its' host. While some early forms of Walkers possesses two arms with sharp claws and two legs.
Walkers are considerably large, this made the Walkers to have a strong attack and its best to stay away mostly from them and reduce their health from afar, the best thing to use against them is the shotgun and the MP 5. Because they are second stage Things, the only way to kill this monstrosity is to incinerate them with a flamethrower after weakening them.
The Brute Walker is considered to be the first form of the Walker. Its appearance is quite brutish, but despite its physical form it possesses remarkable speed and grow into enormous forms. They are equipped with sharp claws on each arm and they don't seem to possess any visible eyes or mouth. They are also capable of producing Scuttlers.
This Walker form is considered to be the form of a fully transformed Walker, although they still have some traits of their early form, they have extended claws and arachnid-like legs, and the tails they drag behind them are actually armless human torsos. Once enough damage is dealt to them, they have a special transformation where a head with a visible mouth with sharp teeth emerges from its split head. This head grants them a special attack, where they lunge forward and bite, dealing nearly one quarter in damage of the whole health bar.
A rare form of the Walker. Not to be mistaken with the Dog Beast. Its appearance quite resembles an ordinary Walker except for its head, which resembles a dog. Unfortunately, the "Cerberus" variant with three heads shown in the picture appears only in the beta of the game (notice the other clothes Blake is wearing and also the fact that in the Strata Medical Facility there are only 1 regular and 3 brute walkers). However, one different Dog Walker with a single dog-like head appears in the Strata furnace facility.