Immediate Interrupt; Trigger: You or an ally is attacked by a creature.
Does a ranger need to call this interrupt before the attack roll, before the damage roll or can he do it whenever he wants? If he can do it whenever he wants, it seems problematic that he can save it for whenever the ally receives near-max damage from an enemy. If he has to call it BEFORE the damage roll, or even before the attack roll, the window of opportunity seems problematically small, especially with a GM who usually rolls attack and then damage behind his screen and exclaims "the goblin stabs you with his dagger and does 15 damage".