heal the guy fighting the dragon... and keep you and him alive, he will kill the dragon slowely... if he doesnt bug that is... i had to redo the quest 8 times untill it worked and i couldnt damage the dragon myself.
did you manage? what i did was:
i entered threw a HoT on him, then healed him with some normal spells and the enemy would come to me, then i healed myself and let him do the fighting.
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