Cube built around the companions. There are 2 of each companion and a lot of the cube is built to synergize well with them but you can still make a great deck without one. I suggest using the old companion rule for every companion but lutri to encourage players to try to draft the companion restrictions. (Old companion rule is you can cast your one companion from the sideboard. New rule is you can pay 3 to move it from your sideboard to your hand.)