I'm level 30-31 and I ran into a single thunder puff, level 23. The fact was it just kept splitting. I was doing the battle for 45 mins and the monster letters went through the alphabet 3 time and back to c again. That's 81 puffs. In the end I had to give up and let myself die or I would have been there all day. Ridiculous!!! Bear in mind I've got to medium healers and two revive ...