Houndoom is a quadruped, canine Pokémon that is mainly black with a long orange snout and an orange underbelly. It has small, red eyes and a black nose. Around its neck is a white band with a small skull-shaped pendant on its throat. There are two white bands on each of its ankles, as well as three rib-like ridges on its back. Houndoom has a long, skinny tail with a triangular tip and three clawed toes on each paw. On top of its head is a pair of long, curved gray horns. These horns are smaller on the female than the male. Houndoom appears near rough terrain areas.