From Bulbapedia, the community-driven Pokémon encyclopedia.
As a user of Burst, Rend can use many of the abilities of the Pokémon he combines with, his Boldore. With the power of Boldore, he can control the earth, allowing him to create powerful weapons with stones. His defense is powerful enough to allow him to easily take a hit with stride and
counter-attack as if nothing had hit him at all. Though his defense is great, it can be broken if the attack he takes is powerful enough.