First some pulls to get the hang of how the mechanics feel in practice, then some to eliminate personal mistakes. Then an extra healer, because the damage is just impossible to heal through, only to realize it’s in fact bad handling of the debuff that’s holding us back. Once that is fixed an enrage wipe. Next raid some toying around with the tactic, but then back to basics, fair few attempts to fine-tune everything and then a kill.
Somehow we can’t force ourselves to really consider Immerseus a proper heroic kill, however Protectors felt appropriate for an early boss in hard mode. We are glad to have it done in first week after killing Garrosh.