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First look on Riot's Xerath Runeborn skin rework on PBE! Huge changes accross all his skills,animations etc. Keep in mind that lots of stuff is missing like particle effects and much more stuff. Also numbers and even skills and spell effects are subjects to change since this is the first touch on this new kit.
The updated post from Xelnath regarding all the changes can be found here:
http://forums.na.leagueoflegends.com/board/showthread.php?p=42112183#42112183