To do this attack: <--- charge ---> Punch , for example, keep pressing Back for two seconds and then quickly press Forward and any punch button. You can also charge Back while crouching (keep pressing Down and Back) or while jumping (press Back after you jump) to charge an attack without moving.
To perform Akuma's Super Combo, quickly press Light Punch twice ( the X button in the 360 version), tap Forward then press Light Kick ( A) and Hard Punch (Right Button) at the same time (it works). To perform the Ultra Combo, do the same thing but press Back instead of Forward. It will become the easiest Ultra/Super Combo to pull off once you've practiced a little bit.
Edited 9 months, 1 week ago