Just sharing my notes from one successful kill with 4 people involved.
Rule 1: LEAVE YOUR DRAGONS HOME. This will be clarified in Rule 2.
Rule 2: Corpse skin! The Corgul that we killed had an average resist value of 88 points. That means that corpse skin moved its physical resist to 100 and its poison/fire resist to the low 70's.
Since we were 3 mages and a tamer, it worked for us.
Rule 3: Rune beetles are nice too. I love my beetle. It died a few times, but that was from lousy cross healing. The dragons were actually harder to keep alive than the beetle. I can't figure that one out.
Rule 4: Cross heal. Yes, it's part of all of my guides, but it always bears repeating.
Rule 5: Melee with fire based weapon (or consecrated), armor ignore and mana leech beat everything else there. Seriously, everything.
But any template, if played well, can help out.