Drop a Clockwork Bomb near the crab, then detonate it to flip the crab on its back. Use a weapon to damage the crab once or twice. After two or three rounds of doing this, the crab will lose its cannon and can be flipped using either the same method or hit with the ground smash from the Hobby Horse. Repeat the process until it has been defeated.

Use the Hobby Horse and keep hitting the crab. Then, use your Vorpal Blade once the crab is knocked onto its back. You can also try using the Tea Cannon against the crab.

To kill the Cannon Crab in the mini-game, just drop an exploding barrel on it or shoot a cannonball at a nearby explosive to blow up the crab.

Use the umbrella to knock the cannon back at the crab. Then, attack the crab while it is on its back until its arm is ripped off. Then use the Hobby Horse and one more Vorpal Blade attack to kill it.

Throw a Bunny Bomb at the Cannon Crab and set it off. This will flip the crab on its back. You can now attack its underside with any weapon. Be careful, as the crab will get back up fairly quickly. Once you have hit it a few times, be ready to dodge or throw another bomb.