I've just wasted a solid chunk of my life, trying to complete 'The Sacrifice' mission, twice. I get to Balthazar, Balthazar fights me for a while, applies the permastun, there's no way to escape the aforementioned stun (no special skill etc), and, when dead, the 'retry from checkpoint' button ejects me from the mission. I play as ranger, a soulbeast. Right now a somewhat sore beast.