FusionDex

Primejask wings beat at the same frequency as their heartbeat, whirring faster and faster as they grow angrier. They are able to land flurries of punches on their opponents, racing past their foes' defences but leaving them open to counter-attacks.

Because it darts about vigorously at high speed, it is very difficult to see. When it becomes furious, its blood circulation becomes more robust, and its muscles are made stronger.