The down air stall (sometimes referred to as WindWaking) is an exploit that allows character wtih a stall-then-fall aerial (with the exception of Ivysaur to float in midair.
Description
Although it was discovered with Toon Link, the glitch is not exclusive to Toon Link. In fact, it may not be considered a glitch at all. It is an exploitation of the way that Brawl's physics engine works. If a character who has a stall-then-fall aerial performs their dair (or in Ivysaur's case, a uair) at a certain height they will lag and hover for a while.
How to perform
Using the down aerial repeatedly after being thrown or otherwise launched into the air will eventually cause the character to perform a small hop, then float in the air for a short time in the normal position for their dair.
Application
Since its movement can be controlled while the player is stalled (like Peach's Float), it can be used as a recovery technique to glide back onstage (see the video below).
Video
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