Taking the locket he presented, Bellatrix turned over the cool metal in her hand. Brilliant sort of magic, really. The sort of disguise they could fashion would be undetectable. Because the locket would bind her blood with a sliver of Kastra Yaxley's soul, not even Ministry wards would be able to identify her as Bellatrix Black. With hungry anticipation she touched her wand to her left thumb, pressing her finger into the flesh behind the puncture squeeze out blood into her now open locket.
Watching Lucius prepare, her face held a sort of barely contained delight. She so enjoyed proper company on such a task, and kept her eyes on his movements. Kastra had let out a soft cry, or would have if she were capable of making sound, which was expected. What was not was the way Lucius hit the floor. Head snapping around, her lips parted in shock. Rounding back on Elias with wand aimed, she could see his chest rise and fall with his impossibly still present breathing. Unconscious, not dead. Turning back to Lucius - but this made no sense.
Bellatrix dropped to a knee beside Lucius. He was still alive. If the curse had rebounded, at least that would have made some sort of sense - but there was no conceivable reason for casting the spell to have this sort of effect. Frowning at him, she gave his cheek a very light slap, wary of trying a spell on him.
"You all right?" she inquired sharply. Their only other company was hardly a threat.
A sudden fear spiked in Bella - maybe this was a coincidence, maybe there was simply a time limit to their revival. Still, Lucius had come back much earlier than herself, so surely she'd have more time to try to sort it out.