Evolution. Deino evolves into Zweilous at level 50, and then into Hydreigon at level 64.

Why does Deino evolve so late?

3 Answers. The creators wanted to make a change and make it harder to obtain good Pokemon. Previous pseudo-legendaries like Dragonite, Tyranitar and Salamence typically have very high evolution levels of level 50+ for the final stage. But in B/W they made it even more difficult.

How does a Deino evolve?

To evolve Deino, all you have to do is to feed it with 25 candies and it evolves into its next form, Zweilous.