Zombie dog/doc

Good at catching non-zombie humans, such as the player, and forcing them into battle. Without a terrain or vehicle advantage, the zombie dog WILL catch up to you.

Upon seeing one, unless your character is well equipped and/or proficient in combat, it is a good idea to retreat to the nearest bush or window and defend from there. While this applies to all enemies, it's especially true for zombie dogs as, once they detect the character, they will catch up very quickly. Many inexperienced characters have died from fighting zombie dogs, whether from incapacitating pain or that deep bite - and, as a result, dying from subsequent attacks by other zombies or simply infected wounds.

Development history

Early versions of DDA, along with the Whales version, included a "Fresh Zombie" which was capable of catching the PC and forcing them into a melee fight, buying time for the rest of the horde to catch up. The zombie dog is essentially the same critter.