Similar to Captain's Mode from DotA, Riot has finally made an official game mode where you can now play as your preferred role or start a game with your preferred make-up.
Team builder is a new game mode that was featured awhile back and the first of many experimental, "limited time" modes that will now allow you to either create a team with an ideal composition or queue as a role and a lane and get in a game with others who are allowed to choose their ideal roles.
Currently, this mode is only enabled in normals and ranked will be played in the typical Draft format. Some controversy has arisen such as Riot "enforcing" a meta with this mode, although it has been a MOBA/ARTS staple for the greater part of a decade. The mode is currently live on NA and EU with more regions to follow.
