Rover

Smasher is the name of a mysterious ball-shaped creature, which is a recurring mini-boss. It appears in Link's Awakening and Oracle of Ages. To attack, it attempts to pick up a heavy sphere and throw it at Link in an effort to incapacitate him. Link must throw the sphere back at Smasher with his Power Bracelet, slamming the creature into submission.

Link's Awakening
Smasher is found in a hidden room in Face Shrine, in one of the "eyes" on the dungeon map. The only way to access this room is the open the wall with bombs. The L-2 Pwer Bracelet, found in this dunegon, is required to lift the ball and defeat him.

Oracle of Ages
Smasher is found in the Crown Dungeon on Rolling Ridge. The only major difference from its Link's Awakening incarnation is that it can teleport the ball anywhere in the room. Also, only the L-1 Power Bracelet is required to defeat it, because the L-2 Power Bracelet is not found until the Ancient Tomb.