# I will make my arrows drunk with blood, and my sword will devour flesh with the blood
Yahweh speaks of arrows as if they were people to whom he could give alcohol and make them drunk, and of a sword as if it were a person who was so hungry that he would eat an animal before draining the blood out.
# from the heads of the leaders of the enemy
A possible meaning is "from the long-haired heads of the enemy."