Dark Knight's level 6 AoE spell Unleash is not consuming stacks of Blood Weapon or returning MP, despite Blood Weapon's description. However, its combo spell, Stalwart Soul does in fact consume stacks of Blood Weapon and restores the proper MP.
Date & Time: 10/22/2023
Frequency: Always
World name: Hyperion
Character name: V'carun Sol
Class/Level: Dark Knight lvl 67
Party or solo: Everywhere
Steps:
1. Activate Blood Weapon
2. Use Unleash