Osiel Cárdenas' brother, Antonio Cárdenas Guillén, along with Jorge Eduardo Costilla Sánchez ("El Coss"), a former policeman, filled in the vacuum left by Osiel and became the leaders of the Gulf Cartel. The death of Antonio allowed for Costilla Sánchez to become the co-leader of the Gulf Cartel and head of the Metros, one of the two factions within the Gulf Cartel. Mario Cárdenas Guillén, brother of Osiel and Antonio, is the other leader of Gulf Cartel and head of the Rojos, the other faction within the Gulf Cartel and the parallel version of the Metros.