Final Cutter

Final Cutter is an ability of Kirby's that's found in the Kirby and Super Smash Bros. series. In the Kirby series, the protagonist would gain this ability if he inhaled a Sir Kibble, while in the Smash Bros. series he had it automatically.

Kirby series
When Kirby engulfed a SIr Kibble, he would gain this ability. He'd be able to thrust sharp blades at his opponents in any direction, though would lose the ability if attacked. In later games (notably Kirby's Dream Land 3) he'd gain this ability when he sucked in a Kaper Bukiset or a Poppy Bros.

Super Smash Bros. series
In the Super Smash Bros. series. Kirby is capable of using a cutter, jumping high in the air then pounding the ground with it, which will send a shockwave through the stage as well.