Hello, I am a KAT Player, and I do exceptionally well with this build; you get about 750 AP at the end of the game with all items. It may say that you only get 512.63 AP at 18, but with the extra masteries you get to 700 AP. Then the Elixer gets you another 50 AP. You get about 200ish HP from spell vamp, maybe more with shunpo. Over 250 DMG per knife with Ult. I dont know if I got the skill sequence right, but you should max shunpo, then bouncing blades, then killer instincts. Use killer instincts with shunpo.