wondering similar things as well. based on my reading, it sounds like 1 to bind demon is good to start and prioritize maxing the other skills that aren’t Blood Oath. Then max Bind Demon and then Blood Oath for any leftover points as the end / which basically won’t be until very late levels.
but, would love someone more knowledgeable to confirm / recommend
I'm testing this in single player. You must get bind demon to 20 soft points to get all 4x auras. Just tried cs with this build, it was good until Diablo. Used 2x defilers and 1x Venom Lord, Blooc Boil to damage, Engorge to heal them. Left click Death Mark, right click Blood Boil. The Venom lord died at Diablo, barely cheesed a kill by blood boiling my defilers.
https://maxroll.gg/d2/d2planner/tjeysy0h