Selena lifted only one finger to block the Essence javelin. That was all she needed.
Michael breathed heavily. His hair stood up to its end, and he broke into a cold sweat. Using the Major Seals was draining. Even though the Wolf Curse and World Serpent chose to help him, they didn't even consider giving him some of their curse power. Michael had to use the bits of curse power that naturally accumulated within active Seals to unleash the Major Seals.
Fortunately, that worked out better than expected. He was drained, but his entire being was overflowing with power – until he threw the Essence javelin, that is. He deactivated the Cursed Seals and Serpent Seals right away. Simultaneously, Michael stopped utilizing Foundation Break and his other Soultraits. He was drained of curse power, and energy, and he didn't have much lifeforce left either. Foundation Break drained too much at the highest level.