Dark / Fire
It powers up Fire-type moves if it's hit by one.
The Pokemon awakens quickly from sleep.
A Houndour was killed in battle, as opposed to fainting (Much like Gary's Ratatta) and was buried in Lavender town. Its trainer visited every day to remember their lost Pokemon, and Arceus heard his cries, but unfortunately, the revival process didn't work as Arceus wanted, and Houndour came back more evil than before. However, this is not its only form.