Watch out when Kirby shoots his mouth off -- the combo will allow Kirby to fire up to three missiles from his mouth at a time.”
— Description • Nintendo Power (Volume #134)
Tri-Missile Attack is a combo ability from Kirby 64: The Crystal Shards. Kirby can get this if he mixes two Bomb abilities. With it, Kirby fires up to three homing missiles from his mouth. The longer the player holds the B Button, the more missiles Kirby shoots from his mouth.
Kirby fires up to three missiles out of his mouth. They will steer themselves slightly, and try to home in on enemies. On contact, the missiles explode. The amount depends on how long the B Button is held.
Kirby can launch 3 enemy-seeking rockets. Hold the B Button to launch all 3 simultaneously.”
— Description • Official Strategy guide
Kirby fires homing rockets from his mouth. He fires from one to three rockets, depending on how long you hold B.”