Iggy Koopa is a boss in New Super Mario Bros. Wii. He is one of Bowser's eight children. Out of all the children, Iggy is the tallest and thinnest. He has green hair and physic glasses. Iggy is the boss of World 5 (NSMB Wii). Before the fortress battle, Iggy is shocked at Mario's appearance and taunts him. Here, he jumps from between the main floor and the three moving platforms. Iggy shoots green fireballs at Mario. He casts the fireballs faster than his siblings. When you've jumped on Iggy's head three times, he goes to the castle. When you find him in the castle, he is in a baby carriage attached to a Chain Chomp. Possibly the Chomp is his pet. There is a little rectangle that the Chomp goes around. Kamek appears, and increases the Chomp's size. Iggy still casts fireballs. Mario must get behind the chomp and attack Iggy. Every time Iggy is hit, the Chomp turns red, and chases Mario swiftly for a short time. After 2 hits, the Chomp becomes faster. Mario must act quick. When he hits Iggy again, Iggy is defeated. A key appears and Mario can access World 6 (NSMB Wii). Iggy survived the battle. He is seen with other Koopalings helping Bowser get up. However, the castle falls on all of them.