Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
This build I made myself while just messing around in a practice game. I found it quite useful in any game mode (except ranked because I am not high enough to play a ranked game yet). The number one thing to remember is THIS BUILD IS ABSOLUTELY ESSENTIAL TO GET FED EARLY. I modified it so you can do alright without being fed, against those pesky target teams where they target Kat no matter what. But to get the most out of this build make sure you get fed early on.