Around the center of the Wharves chapter is a place where you have to constantly jump across a river with one Rune Knight in each area you jump to. Before you jump, hit the Rune Knight twice with Telekinesis. When you jump, try to make the jump indicator red so that you hit the Rune Knight. While he is on the ground, draw your weapons or get your claws out. Right when he stands, start attacking and catch him off guard. Two hits should be required with bare claws and only one hit with some sort of weapon.