Edge momentum shifting
The Cape glide, or aerial cape extension, is an advanced technique used for Mario in Super Smash Bros. Brawl. It is the act of Mario dashing off the stage and using his running momentum with his cape to reach great distances of the edge. Donkey Kong can also perform this technique in the same way Mario can using his side special move.
How to Cape glide
Cape gliding (or CGing) is very tricky to perform but, once mastered, can be amazing for edge-guarding. To start a cape glide, first dash towards the edge, then just as Mario goes over the edge, initiate the cape. The result should be that Mario glides out a long distance off the stage with his mid air jump saved. If performed incorrectly, Mario will either barely go anywhere or a slight glide will be produced.
Applications
There are many ways of using the cape glide for edge guarding purposes mostly. All of the aerial moves can be done at this point but what probably would be the most useful one would be his forward aerial meteor smash, because if timed right, the player can always recover with a cape glide and it looks very professional. For Donkey Kong, the side special is the meteor, so it is very useful for spiking opponents that DK would not be able to hit otherwise (his other spikes would be too slow).
Mario can also use the Cape to Cape dash, which is Cape gliding on-stage. This is done by performing a reverse side special in conjuction with a Cape glide, reversing Mario's direction before he glides off-stage. This is only possible on some platforms.
Another use that is a bit trickier but a very good edge guard technique is to do what some call a "F.L.U.D.D. Wall" ("FW"). This is done by cape gliding (assuming F.L.U.D.D. is fully charged) then mid air jumping and then immediately use F.L.U.D.D.. This will cause Mario to fall while using spraying as an edge guard making a "wall". Note that to recover from this, the player must immediately use Mario's up special or else the player will self-destruct. With the right timing, the cape can edge guard on its own just like the stationary cape does.
Using DK's Headbutt for a reverse side special cape glide can be useful in surprising opponents with a meteor smash, if activated correctly DK will perform a headbutt while sliding off the stage and then back on while not using any jumps, this can be useful to meteor smash edge campers.
Additionally, the technique is also useful for quick manoeuvrability on levels with midair platforms such as Battlefield.
Video
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