Personally I go A2 > A3 but specifically for AI I actually leave the A3 off since constantly sheeping one man defenses makes fights take forever.

Yah, the AI is really stupid with him if you don't set it up right. I will chose to go against teams with him on their roster because if not set up correctly they always start with their A1 on Wukong.

I go A2, then to A3. The A3 is to hit the person on their team with stoneskin because most teams are set up so that the person that can save their team has stoneskin. UDK to protect Wukong, a cleanser to remove all debuffs, a reviver, etc. This takes them out of the game long enough to do some damage. 

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