Normal punch - more variety

[Alblaka]

@ YinYin: Not for a player, that is.
But one could add an additional complex key input (f.e. dja) in the first punching frame, which leads to a kick frame (left and right respectively). Then code an AI which randomly chooses one of the attacks.
Alternatively, you could create a dummy object to replace the character, add the AI to the dummy, have it perform a random choice and then base the characers move on that choice (issue would be the noticeable 2-tick delay, if not more.)