I made it to the dragon with my lv 8 team after playing the game for about 3 weeks since installation (evenings/weekend only).
I have spent a little money (<20 $) but enjoyed myself. Team is war, cleric, mage, ranger, mostly epic gear except when common/rare is better.
The dragon breath weapon killed all the toons except the warrior in the first round.
What level is needed to get the kill? Think the dragon was lv 15