Anybody got any other ideas? I have two:

1) One where the player assumes a neijin-like stance but instead of the attack power increasing, the defense increases. For example, when first triggered, blows landed by the opponent do only 80% damage. This slowly decreases in time and, like a neijin, has a refractory period in which it cannot be used again. One of these moves could theoretically cancel out an opponent's neijin.

2) Speed increases. Now just in case the player's thumbs aren't quick enough, it can be implemented in a different way: Slow down the opponent. It's still essentially the same thing - just a change in perspective. The effect does not decrease with time but does act only for a limited duration, of course. Two of these speed-increasing power ups would in effect cancel each other out.

These two ideas are kind of half-baked, I know, but hopefully they will point you in the direction that I'm hoping this thread will go.