Hookbill the Koopa

"It's m-m-my job to b-beat Yoshi, and I'm a g-gonna m-m-make m-mince meat out of that c-cocky little wimp!"

- Hookbill the Koopa

Hookbill the Koopa is an enlarged Koopa Troopa in the game Super Mario World 2: Yoshi's Island. He is the boss of World 4 and resides atop the final castle in that world. When Blue Yoshi and Baby Mario reach the bridge on which Hookbill is fought, a fog envelops the area, dissipating on the other side. Blue Yoshi and Baby Mario then encounter Hookbill and Kamek. Kamek threatens Blue Yoshi by saying "Little Koopa come through for me now! Go forth and rock Yoshi's world!" and then casts a magical spell on Hookbill. Hookbill retreats into its shell, which grows into an enormous size.

After the transformation is complete, Hookbill re-emerges from its shell. Walking on all fours, it creeps towards Blue Yoshi to attack him and Baby Mario. After walking on all fours for some time, it stands up and runs in Blue Yoshi's direction and lunges at the dinosaur. Blue Yoshi then must dodge the attack in order to avoid getting hurt. To defeat Hookbill, Blue Yoshi must first throw Yoshi Eggs at its head or arms. Jumping on Hookbill's shell or head will cause it to cough up eggs for Blue Yoshi to use should his supply get depleted. After four hits while on all fours or after two hits while on two legs, Hookbill will fall backwards and will be briefly vulnerable to attack. Blue Yoshi must jump on and then ground pound Hookbill's exposed underside, delivering damage to Hookbill. After this (or after a certain amount of time passes), Hookbill will recover, retreat into its shell, and begin pounding the ground. It will then re-emerge, and the process will have to be repeated. Once its underside has been pounded three times, Hookbill is defeated. Its shell explodes, and Hookbill falls from the top of the castle.

Hookbill the Koopa re-appears in Tetris Attack as one of Bowser's allies in the game and speaks with a stutter. Here, it takes Phoenix's place of the original Panel de Pon at Stage 9, and it should be noted that unlike other characters, Hookbill does not have a personal ally of its own.