>>11236414It's something of an exploit of how Melee's physics engine works. You do it by jumping, then just a few frames later air-dodging diagonally either backwards or forwards toward the stage. The way the engine is designed, when you air dodge close enough to the floor, it's made to transfer the momentum of the air dodge into lateral movement across the floor, though how much you actually move depends on how much friction the character exhibits. In other words, the more slippery the character, the more the momentum will translate into distance traveled. This is best seen with Luigi, as he is by far the most slippery character in the game, and as a result, his wavedash is fucking ridiculous and will take him about halfway through Final Destination when performed correctly. Meanwhile, Bowser has a fuckton of friction, and so he will get absolutely nowhere with a wavedash. There's another catch to wavedashing, however, in that how easy it is to perform is highly dependent on how many frames a character takes to actually jump after inputting a jump. Some characters have longer jump frame time values than others, and so you have to time the air dodge just right with them (Link and Bowser come to mind), whereas others jump damn near immediately, so it's much easier to wavedash with them (Marth and Fox are quite easy by comparison to the aforementioned slow jumpers)..
