Nothing went as the group expected. At first, the mission seemed easy enough as they harvest experience points easily through raining down the [AoE] skills down the [Rift]. Indeed, even with some monsters being much more resilient, it wasn't much of a problem as the elites were still able to take these down. But things got complicated once they entered the cave, an area which couldn't; be reached by their skills.
This is proven by the return of Quinn and his allies who have finally reached the boss of that area. It was a monster which they have still failed to identify, wielding what seemed to be limitless chains that required Quinn to continually use one of the strongest skill at his disposal.