I want to return champion.
how can i do thet
You're responsible for buying that champion. You can't just buy a piece of gum and eat it, and a week later say "I want to return this gum".
However, if you make a support ticket, you are able to get a refund on ANY 3 Items including champions/skins/runes bought with either IP/RP. You can only do this one time though.
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