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.
First i start off with Amplifying Tome to upgrade -> to a Hextech Gunblade.
After that im done with my hextech, i choose to buy sorcerer's shoes to gain some magic penetration and movement speed to chase up with others or to escape fast and survive. U might want some more spell vamp and life steal so i choose Will of the ancients.
Now you might want some bad damage, which means u choose to start building a trinity force. And now i think u want to get even some more dmg,ap and lifesteal+spellvamp, so i build 1 more hextech gunblade.
Now if you want some survivabillity u shall buy a guardian's angel to survive fights and make a good escape and become a great warrior.
U shall pick Exhaust, Ignite to make some BIG damage and have a good chance to gank/escape.