Anyone whining about Kat obviously haven't mastered the remake. (Btw for the QWER comments, it is QEWR at the very least -_-) There is plenty that goes into differentiating a good Kat player from a great Kat player. Positioning is a staple for excelling as hard cc wrecks Kat's ult which is her main source of damage. Now, within a teamfight after you ult you get a few more decisions. Pending on different scenarios such as an assist reducing your cd's you must decide on whether stopping your ult early to use your e, q or w will yield more damage. To truly play Kat at an optimal level you must make quick decisions throughout the course of a teamfight due to her high risk, high reward nature. Being in the correct position prior to ulting and choosing when to stop it and shunpoo to continue your cd reduction and finish your combos prior to finding a good position to ult again. Also, if the enemy team is at all competent, timing is also needed skill. As I previously stated, hard cc shuts Kat down so when you enter a teamfight is crucial. There are many ingredients that go into playing a champion, but Kat seems to be fairly balanced as any given game she can be shut down or go hyper carry. Builds vary as much as any ap carry where your build adjusts to team comps and game to game situations. That's just my 2 cents as an avid Kat player who has also seen the fine line between normal people's play and Scarra's.