Whirling Fortress

Whirling Fortress is Bowser's up B move. It has several unique properties that make it highly beneficial to Bowser play:

• It has very little startup (5 frames), during which Bowser is invincible, and has relatively little cooldown lag.
• One cannot get shieldgrabbed if one cancels a Fortress directly into another.
• It hits throughout most of its animation (on the ground)
• It allows Bowser to move quickly and suddenly in one direction
• It has high knockback on the ground, and inflicts high damage in the air
• It has high priority
• It can be used to edgeguard quickly and efficiently (Fortressing off the side of a stage leads directly to an edge-hog)

The above properties make the Fortress, as it is usually called, a versatile move. It can be used a damaging replacement to Bowser's quick, but laggy, roll. It can be jump-cancelled out of a shield to discourage overly aggressive opponents. It can be used to clank just about anything with decent timing. And yes, it can be used to recover.