Mega Goomba (boss)

Mega Goomba is the boss of World 4 in New Super Mario Bros.

In a quick cut-scene, you see Mega Goomba gain access to a mega mushroom, and it's your job to slap the key right out of him!

First, you must activate a switch, and 2 platforms will appear. When you stand on the platform, it will elevate for you, and stay there. From there, you can either wall jump, or jump directly to the mega goomba. For the attack to be useful, you have to do a groundpound, on any size under mega mushroom.

Once you hit him 3 times, he will die, and you can get the key to world 5.