The eternal championship is actually broken. Ridiculous amounts of damage, broken mechanics, one shots from nowhere. I wasted my entire night on this garbage. Whoever designed these boss fights needs to be fired immediately. They are an absolute incompetent.
EDIT-After looking into this a bit more I am depressed. The problem is even worse. Quite simply level sync and low stats on 7.0 gear have made us significantly weaker than these bosses. They should have been adjusted to compensate, but no that would be logical. Good job devs. You guys are pro.