The strategy ravage mentiones works really good, though I have one thing to add to it: make sure you have either the healing spell of the healing ghost. As a dragon, you generate mana really quickly. So when you're low on health, fly away, regenerate some mana, land on a platform and turn human, heal yourself, get back up in the air and regenerate mana!
At the low levels you can get beauten up pretty quick, so save often. It's really worth the risk, all those experience points!
