Waveshine infinite
Guide to the Infinite Combo
How to Infinite Combo
The only character that can infinite combo is Fox. In order to infinite combo, you use Fox's Dair (down-air) and l-cancel it, then use his Shine and wavedash out of it. Then, you repeat. This combo is extremely hard to pull off, and takes a considerable amount of practice.
There is also an infinite combo when you get on the edge, triple jump (so you just hit the edge again, when you just move into it without actually finishing it and firing), fall, shine, jump cancel the shine, and repeat.
The Technicalities
The infinite combo is very powerful. The damage sustained can be 999%, thus the name "infinite combo." Characters like Link, Peach, and Zelda cannot escape this if the Fox is skilled enough. On the down side, not all characters can be infinite combo'd. Certain characters slide too far (from the Shine) in order to be caught again by the Dair. Some characters are even knocked down from the Shine, and unfortunately, you can't infinite combo a character if he/she is on the ground.
Other Infinites
Wall Infinite
Against a wall, do a L-canceled short-hop Dair, into a shine, and repeat.
Land Infinite
Waveshine into another shine and repeat, hitting your opponent each time. Can only be done against characters that only go about as far as Fox's wavedash allows him to.