In terms of the mains vs pure actions within that rivalry, I have heard a mix between both sides. I don't know what is true and what isn't unfortunately. All I do know, the rivalry shouldn't had such a big amount of mains in beginnings of it. In terms of clans and their involvement, at least in my own point of view. Its hard for Supremacy or Terror to admit who may be calling mains or if these respective main clans have leaks within one of the rivals. Both sides over discord have blamed each other for the main clans hitting each other's fights etc.