C.O.R.E.

C.O.R.E. is stands for ( Call Of Relentless Evil ) was a villainy organization that able destory whole Valoran by ruins for good in the Centurions World, but only was been there which was stated by Mohs one of the summoners told this about The Core Forces will is to able destory the World and the League of Legends itself that protected Runeterra for many years