Schnook

It knocked out most of my party almost instantly, but I managed to kill it with a druid and a rogue. Started with a wall of thones and continued to use every DoT AoE I could find, when the dragon got to close I moved in with the rogue and tried to move it away from the druid. 1-4 tick damage from about 6 different sources killed it in 2 or 3 minutes. No idea how to win this fight without cheesing it though.