Mightyena

Mightyena (グラエナ Guraena) It is a -type Pokémon. It can be found in the Hoenn region. It is quite a fierce Pokémon that travels in a pack and will only obey a trainer that it sees good enough to be its trainer. Its powerful attacks includes Crunch, Ice Fang, Thunder Fang, and Fire Fang.

Evolution
Mightyena is the evolved form of Poochyena, Poochyena evolves into Mightyena once it reaches level 18

Trivia
(Part of the above Trivia has been removed, as the topic was changed from Umbreon to Hyenas.)
 * Mightyena is one of only seven pure dark types. The others are Umbreon, Poochyena, Absol, Darkrai, Zorua, and Zoroark.
 * Mightyena very strongly resembles a wolf.
 * Though it strongly resembles a dog, it is actually a hyena, meaning it is more closely related to a cat.