Landing lag glitch
The landing lag glitch is a glitch in Brawl that causes certain characters to suffer lag under conditions that should not cause such lag. Specifically, certain special moves that place the user into helpless can have their lag "saved" if the user grabs an edge after using the move but before landing. The next time the user lands on the ground, even if doing it by jumping from the edge or being hit by another player, they take the lag that would have been applied had the character landed in helpless. The only way to avoid the lag is to drop from the edge and jump back up without grabbing the ledge again. Of course, such lag should not happen because the character does not land in helpless, and such is the glitch - the game doesn't realize that it should forget about applying lag upon the next landing if an edge is grabbed.
The glitch cannot be avoided with specials that doesn't cause the character to become helpless and never disappears until landing on the ground; however it can be "overruled" by using an aerial that has landing lag (though with 35-40% more landing lag than usually would get for landing with that aerial). Preferably, one who knows that the glitch is "set" would use an aerial with lag to override (not completely though) the glitch, but less lag than the glitch would provide.
 Characters affected by the glitch
Except DK and Bowser (both 2 frames), all have 15 frames for soft landing. Hard landing is said below.