Some of the most wild tech from the Smash community in the past came from My Smash Corner, who has, up until now, been largely silent on Super Smash Bros. Ultimate. As it turns out, they were just preparing a video on a game-changing mechanic: Attack Canceling.
Smash Ultimate allows you to cancel the startup of dash attacks, jabs, and other moves with a jump during their startup. This quirk allows players to get access to safer types of aerial attacks, instant b-airs, and for Rosalina players, a brand new combo tool. Check out the video above and get into training mode: If you play Ultimate, you’ll want to know how to do this.
Source: My Smash Corner