The Christmas event is still running lol

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I'm Diamond IV and want to play with my friends who are new to the game. What rank do they have to be in order for us to queue in ranked together? Right now it says the gap is too wide.

5 Days ago I was banned for 2 days for "ILLEGAL VIOLATION". WTF is "illegal violation?!" Then after 2 days I played few hours and got banned again for "illegal violations". Ban expired today, and I played today one hour and got banned for "ILLEGAL VIOLATION". I don't even know for what I was banned! I appealed the ban first time and I can't send any more appeals. But support doesn't answer at all. Are you kidding me? This game is full of cheaters, but you ban legit players?...

i played this game a 151 hour's