I will show how to use this champ.

Because some people think. MORE AP. But its more magic penetration. because if the enemy gots 100 magic resist he reduct 50% of the damage!!! and 25 magic resist = 20% less damage!. But if you lower the Magic resist further to 25- Magic Resist, then you will hit. Test: the champ gots 50 Magic Resist. You will lower with the full build (without runes) 15% of 50=42.5-20=22.5-28= -5.5 Magic Resist. With runes. = -9 Magic Resist! Thats -9/91 = 11% extra damage!!! Now if you hit 500 you hit 555!!!

Your E is very good against minions with all the Attack Speed and AP