In the fight against
it seems like a scripted loss, except the game just ends if you fail. I put together a strategy I thought might work by making sure the spirit preventing control effects goes first and it's just skipping my turns for no reason.
What is the exact only method you are allowed to use to beat this encounter. Which 4 exact party members are needed which the 4 exact classes and exact builds that will work and the game won't just throw a fit and prevent it from working by invisible mechanics like level 8 characters casting level 9 spells or skipping your turns because that is not the scripted method that is allowed to work.