Irelia and Xin are very similar champions. They are both tanky assassins with incredible lane sustain and once they get ahead of you it's nearly impossible to recover. This is what makes them so hard to balance.
The rework increased more of his strengths: mainly dueling and single target assassination.
Passive: Xin already ran 26 Armor Pen in lane and now the extra 15% will make him very hard to fight 1 on 1. It also lets him scale a tad bit better.
His Q got a AD bonus which is useless because no one maxes out Q but moving the cooldown from W to Q allowed them to move the former Passive to W.
W was always awesome and nothing changed.
E was always awesome and nothing changed.
Xin's Ultimate now makes someone MAN THE **** UP. If Xin gets to your carry and hits his ultimate, he's going to get 1-2 seconds to blow them the F UP.
BE A MAAAAAAAAAAAAN
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Realo won gold at the Sex Olympics with a BROKEN FRIGGIN NECK.-Voltch