Appearance:
Boom Boom is a large, spiky-shelled Koopa general with wings. He's the mini-boss of every fortress and airship stage.

Phases & Attacks:
- Phase 1 (Ground Attack): Boom Boom runs back and forth across the screen, occasionally jumping. His primary goal is to collide with Mario.
- Phase 2 (Shell Spin): After being stomped once, he retreats into his shell and spins rapidly across the floor. He is invincible in this state.
- Phase 3 (Winged Attack): After being stomped twice, he often grows wings (if he didn't have them already) and flies around the room, making him harder to hit.
Weaknesses:
- Stomping: The primary way to defeat Boom Boom is to jump on his head three times.
- Fireballs/Hammers: Fire Mario's fireballs and Hammer Mario's hammers can also damage him, often defeating him in fewer hits than stomping.
Strategy:
The key to defeating Boom Boom is timing your jumps. Wait for him to stop spinning or land from a jump before stomping on his head. If he gains wings, try to anticipate his flight path. A Super Leaf (Raccoon Mario) can be very effective, allowing you to fly above him and stomp him from a safe position, or use the tail whip if he's on the ground. A Fire Flower or Hammer Suit makes the fight significantly easier, as you can attack from a distance. After three successful hits, he's defeated, and you'll receive a power-up as a reward.