Sidestepping

Sidestepping, also known as spot dodging or ground dodging, is an action in the  games and in Super Smash Flash 2 that renders the character invincible for a small amount of time.

Functionally similar to an air dodge, it is performed by pressing down while shielding, and can be employed to evade any and all harm of short duration. It is perhaps most useful in dodging projectiles and items, as well as attacks with a low amount of active frames, allowing the player to punish the lag on their opponents' missed attacks.