Furious Fred de Fillet
From the Super Mario Wiki
Furious Fred de Fillet is the boss of World 4 in the game Yoshi's New Island. Fred starts out as a normal Jean de Fillet, but is then enlarged with Kamek's hammer. He attacks by sending lava waves or by dropping Flightless Skeleton Goonies at Yoshi, who then has to ground pound a button on top of Fred's armor to make it fall off. Yoshi can then hit Fred with an egg to damage him and make him angry, which makes him jump around and turn back to normal. The player has to hit him two more times to defeat him.