I've been thinking how to do OTT Kung Fu game mechanics. Mega fights generally build up from fairly simple moves to more and more impressive and outrageous manoeuvres later in the fight. So, Chi should be something that starts off low or at zero, and is built up by doing simple moves until it is unleashed to power the big shots. Kind of like Diablo II and World of Warcraft, where the assassin or rogue uses some moves to gain power-up points, which are then released in "finishing moves". This "Chi" could be something that is scaled like Magic Points, or on a larger scale (e.g. starts off at the level of your POW and then builds up, capped by your Martial Arts skill). Any successful skill use could grant Chi points, including both of successful attack versus successful parry. Or, maybe parrying a blow grants the attacker the damage that would have been done as Chi points.