The assassin still, reflexively, fires a single bolt, which is wasted into the air, hitting a large rock, and breaking, before the three of them collapse to the ground. They were certainly well-prepared, though; he notes several more scrolls in their pouches, as well as quality ranged and melee weapons, and it's clear that these three are not inexperienced fighters; the bolt might have actually<em>hit</em>him, if he'd let it be fired at him, even with his impressive defenses.