Pogobot

Pogobots are enemies found in the Factory area of Donkey Kong Country Returns and Donkey Kong Country Returns 3D. Pogobots are springed robots constantly surrounded by electricity, which protects them from direct attacks from Donkey Kong and Diddy Kong. However, they can be defeated with a Barrel or a Buckbomb.

They first appear as a silhouette in the level, Foggy Fumes. Afterwards, they'll appear normally for there on out.

Reference
Pogobot