It was happening right before Rune's eyes—an inexplicable thing. The small shadow tendril had somehow entered Luna's barrier and was causing it to disintegrate. Rune had to kill the Devourer before her barrier completely disappeared.
His eyes were weak, and his body was heavy. It was a struggle just to keep up his technique, but Rune knew it was nothing compared to what would come once he undid it. As soon as Fusion was released, all that built-up fatigue would come rushing over him in a wave, sending his body into a state of shock and unconsciousness. But at the same time, Rune was not sure if he had enough strength left in him to do what needed to be done and save Luna.