So far i haven't figured out how to deal with them. There's two situations i'm completely stuck at. The first one is with the Red Dragon, he's simply too tough, or i'm doing something completely wrong.

The second situation is with that huge crystal heart, where no less than two dragons spawn. Same situation there, there's no chance of either killing them, or destroy the crystal before they kill me.

So i guess my question is...what's the best way to deal with these creatures. Are specific partymembers required perhaps ?

When you get near the crystal run to it to start the cut sceen cinema then you can attack Nolaloth or
leave but if you attack you have the 2 Black Dragons
You need to Cast Mordenkaidens Sword and a summon VII creature to attack one of the 2 Black dragons to
keep it busy while your Team all attack the second.