Hydreigon is a Dark/Dragon-type Pokémon from Generation V. It is the final form of Deino and evolves from a Zweilous at level 64.
Hydreigon is a large three-headed draconic Pokémon. It is mainly blue with black scruffy fur covering its arms and neck. The black fur that covered up its eyes as a Deino and Zweilous has disappeared, creating a frill-like appearance and is now magenta in color. Instead of having one wing-like appendage on each side of its body, it now has three wings on each side of its body that allow it to fly. On the end of each arm is a smaller blue head with eyes and a mouth, but no brain. Zweilous uses both its main head and its head-like hands to voraciously devour its food. After Zweilous evolved, its tail has grown longer and has magenta scales on the underside as well as a black tip on the end. Its round, plump belly has two rows of magenta scales just like it had when it was a Zweilous. Its abdomen seems to have grown plumper and fuller as a result of eating so much food as a Zweilous.
Hydreigon is said to be a violent and brutal Pokémon that devours and destroys everything it sees. However, it appears to be harmless and loyal when raised and owned by a skilled trainer. As seen in the anime, it will allow its trainer to ride upon its back and fly. In Pokémon Mystery Dungeon: Gates to Infinity Hydreigon is a wise and very kind Pokémon who represents and embodies the Voice of Life; he is endearingly quirky and will assist the hero throughout the game.
In Pokémon Mystery Dungeon: Gates to Infinity
Hydreigon is the Pokémon form of the Voice of Life. At first he appears to be evil when he is chasing Munna in the player's vision. In fact, Munna tricks the player that Hydreigon is evil when the player encounters him. Hydreigon tells the player about the Bittercold and saving the world. After beating the game, he joins the players team.
- Black - A brutal Pokémon that flies continuously through the sky on its six wings, marking everything that moves as an enemy and attacking.
- White/X/Omega Ruby - The heads on their arms do not have brains. They use all three heads to consume and destroy everything.
- Black 2 and White 2/Y/Alpha Sapphire - It responds to movement by attacking. This scary, three-headed Pokémon devours everything in its path!
- Sword - There are a slew of stories about villages that were destroyed by Hydreigon. It bites anything that moves.
- Shield - The three heads take turns sinking their teeth into the opponent. Their attacks won't slow until their target goes down.