In AOM Ragnarok is a power that can be cast and it changes all of the player's units to heroes of Ragnarok. In 0 A.D., it could be a powee that is cast and it turns all the players infantry to Marian Legions.
I realize I should've done this ages before but I updated the first post with some sort of design document (the buildings, unique technologies and team bonuses are not added yet)