Enter the Kobold is a tough quest regardless of class. Even on normal. Reaver's Refuge quests are all like that, though not to that degree. Inspired Quarters (both packs) are much, much easier.

The best strategy I've found is to circle down below the platform that the boss starts on, heal, then run back out. Focus on the bosses first, as the mobs respawn. Living Spells are considered oozes. Ooze Puppet is a spell.