Due to the White Scars having such a prominent place in the Secession and proper rules for them probably being a few years away we have a new Rite of War to represent armies that are mostly if not entirely bike mounted.
Rite of War: Thunderous Strike
*Legion Outrider Squads may be chosen as Troops or Fast Attack
*Legion Attack Bike Squads may be chosen as Heavy Support or Fast Attack
*Legion Jetbike Sky Hunter Squads may be chosen as Elites or Fast Attack
*Only models able to move 12" in the movement phase or start the game mounted in a transport capable of moving 12" in the movement phase may be selected.
*no fortifications may be selected.