Boss Brolder is a large rock monster that rolls around the arena. To defeat him, pick up the smaller Brolders he spawns and throw them at him when he's vulnerable (not rolling). After each hit, he'll become more aggressive, rolling faster and spawning more enemies. Be careful not to get crushed by his rolls. The Fire Flower can also damage him, but throwing his own kind back at him is more effective. Three hits will do the trick.
