According to Fusible there may be a new Leauge of Legends Game Mode soon.
RIOT Games registered a diversity of domains containing League of Legends Supremacy, spellmistakes of the name and the short versions of it. And RIOT Games got the Supremacy.com and .net domain a few days ago.
This seems, like RIOT Games is planning a new game mode for League of Legends. There may be an offical news soon.
Original link: http://fusible.com/2012/04/supremacy-com-new-league-of-legends-supremacy-game-mode-is-on-its-way/