Zweilous is a new pokemon in Pokemon Black and White. Zweilous is a Dark/Dragon type and can not be caught in the wild. Zweilous evolves from a Deino at level 50, which then evolves into the powerful Hydreigon at level 64.
Deino is the only pokemon in the evolution chain that can be caught in the wild, so you’ll need to catch it to get Zweilous and/or Hydreigon.
