If Kha kills Rengar he gets a 4th evolution point flipped around Rengar gets a maxed out Bonetooth necklace and you don't need to kill your nemesis alone your team can assist you. Good huntin!
If rengar kills kha'zix with a bonetooth on, hes gets that head.
If kha zix kills rengar, kha zix gets a 4th evolution point (normally he gets 3)
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