World 5-Castle (New Super Mario Bros. Wii)

Iggy Koopa's Castle. The player has to cross lava by means of grabbable grate, some of which is round and spins and some that retracts back into lava or walls. Green spells also attack from off-screen. The boss battle has Iggy with his pet Chain Chomp, which grows after being assisted by Kamek. It drags him around the room, and Iggy, who is riding in a seat attached to the Chain Chomp's chain, occasionally shoots spells. There is a platform in the middle of the rectangular stage with two Donut Lifts, and four White-Green Checkered Blocks, two on each side of the room. When Iggy is attacked, the Chain Chomp will glow red and jump in random directions. When beaten, Iggy will run away and Mario will progress to World 6.