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.
For this build to work to its fullest extent you need to get at least 1 kill before getting to lvl 6. Try to stay back and harass the enemy with your large crit chance/damage you'll keep them at bay, and it will be very easy to get a kill if they try to run away. Play defense, Play smart
I hope you win GL HF