10: Demon Blood

This is the 10th Ingredient of the antidote needed to wake up Angel. The Verse describing the ingredient mentions demon sap, obviously referring to blood. While the heroes aren't aware of this, they've gathered it in episode 18, when Queen Dark (disguised as a knight) challenges Argaï for a fight to the death. Although neither of them die, Argaï knows to injure the Queen at her arm. In episode 19, reading the next verse, they know they got lucky getting a blood-sample of the Queen! Maybe Blood of Queen Orial would have been fine too. At the end, they use the blood in the Final Ritual to let it burn, also hurting the Queen.