So the dragons are badly bugged.
1) It looks like the agro rules changed on the breath weapon to be similar to those used by archers and other ranged attackers, however, the animation is not in sync with the targeting change as the dragons target the healer (which is the default target of all the ranged classes). Thus it appears that the dragon is hitting a much larger cone than his red area and animation are showing. In fact, he is just changing targets to the cleric and the animation is not displaying this. This becomes obvious when the cleric dies in Malabog castle and the dragon walks to the door and stands there doing nothing following the healer
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