Across all of pro play in season 9 (preseason, spring, summer), Garen is now officially the only champion with 0 picks and 0 bans. He is also one of only two champions that have never been picked (the other being Amumu, with 0 picks and 6 bans).
Source: https://gol.gg/champion/list/season-S9/split-ALL/tournament-ALL/patch-ALL/role-ALL/league-ALL/
EDIT: Seems like the website isn't fully updated, and it's possible EVERY SINGLE CHAMP has been picked or banned in pro play this season! Might be more interesting to follow which haven't been P/B in the top 5 leagues (LCK, LPL, LMS, LEC, LCS): Rammus, Teemo, Brand, Udyr, Garen, Wukong, Nasus, Shaco, Amumu, Tryndamere, Diana, Warwick, Katarina, Illaoi
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