Chi is the secondary resource common to all three monk specializations in Mists of Pandaria. It is conceptually most similar to paladins' holy power, as a stored 4-point pool. Through his level 30 talents, a monk can choose to buff chi generation in one of three ways, either increasing the maximum pool size via Ascendance, increasing the rate of generation via Power Strikes, or enabling an ability that can periodically completely refill chi (Chi Brew). For all monk specializations, chi is required in order to use the majority of abilities.
Before I move on, let's make one thing clear: Chi and combo points (CPs) are very different systems. CPs are stored on a single target; if a rogue or feral switches targets and uses a CP-generating ability, any CPs stored on the previous target are lost. Chi, in comparison, is stored on the monk, making target switches much simpler.
Second, most abilities that consume CP scale with the number of CPs used; for example, a 5-CP Ferocious Bite hits much harder than a 1-CP Ferocious Bite. All of the monk's chi-consuming abilities have a fixed cost, though this may change later in the beta.
Chi generation For the Brewmaster and Windwalker specializations, chi is primarily generated by Jab in any of its incarnations (such as Clobber, Slice, or Sever). Energy regeneration prevents using this too frequently. However, windwalkers specialization bonus (Muscle Memory) gives them plenty of chi to work with, while brewmasters will alternate this or Expel Harm with Keg Smash.
Mistweavers are little more complicated, since they rely on mana a great deal more than the other specializations rely on energy. Surging Mists, their large and expensive heal, generates 1 chi, and their channeled Soothing Mists HoT has a chance to generate chi with each tick.
Chi usage This is where the fun happens! Without delving too deeply into class mechanics (that's a topic for another article), each class will have definite moments where they want to spend chi. Windwalkers will frequently use Rising Sun Kick and Fists of Fury as part of their damaging rotation. Brewmasters have several short-duration cooldowns for survivability, such as Guard and Elusive Brew. Finally, mistweavers can AoE heal via Uplift or burst a quick heal with Chi Wave.
Things may change, but as I see it now, you'll want to balance your chi usage and generation so you steadily stay around 2-3 chi and then "spend down" as fight conditions dictate. Whether you need to burst down a target, survive a bosses' special ability, or help someone else survive a bosses' special ability, chi helps you do it.
It's open warfare between Alliance and Horde in Mists of Pandaria, World of Warcraft's next expansion. Jump into five new levels with new talents and class mechanics, try the new monk class, and create a pandaren character to ally with either Horde or Alliance. Look for expansion basics in our Mists FAQ, or dig into our spring press event coverage for more details!