Archer of the Month: Achievement STEAM of Assassin's Creed Origins

Buy the 'Elite Ranger' ability. It makes it so that time slows down when aiming a bow in midair. Jump down from somewhere, aim in midair and shoot an enemy in the head with an arrow. The enemy has to die from this. You are allowed to weaken the enemy beforehand so that he dies in one hit. You can do this in any restricted area / enemy camp, those have lots of enemies.
The light bow works best. It shoots very quickly and is easy to aim.