A rare Riven skin has reappeared following RohanGod's feat

RohanGod has been honored with the 2012 Championship Riven skin, a piece of League of Legends history that few believed would ever return, after achieving the highest rank in every Riot Games title. This player has attained the top level in all of the other Riot-developed games, including Legends of Runeterra, Teamfight Tactics, and VALORANT, although most League players find it difficult to do so. This is a remarkable accomplishment that demonstrates their proficiency in a variety of game genres, such as MOBA, FPS, card games, and auto battlers. 

Championship Riven is frequently mentioned as one of the rarest skins in the game, along with Black Alistar and PAX skins. It made its debut as the first championship skin following Worlds in 2012. It never returned after a week of being sold.