Lucisfear/Story

Lucisfear's appearance is set up by the lore on The Godslayer during the Black Legion arc, and he is first foreshadowed during a series of monologues in between the Caelum-Conclave arc.

Caelum-Conclave
During the second Conclave incident he forcibly summoned himself through the Cronus, momentarily taking form by becoming a parasite to a demon's body before stabilizing his physical shape and promptly executing the demon. He corrupted and shattered Astora's Excalibur (which he'd manipulated with Rapture to trigger a space time distortion similar to sliding), reforging it into his own cursed blade and knocking Astora unconscious. He also triggered Night of Fallen Angels, mass invading reality, including an attack on Caelum. He took over the Cronus and nearly killed Tsukihi before Chaos stepped in with The Last Word. The two of them fought with Lucisfear coming out victorious and missing the execution on Chaos due to the Administrator's intervention. In that same section, he appeared one last time in the Conclave's world to announce his retribution.He appeared once more during the second metropolis section of Caelum, taking advantage of Zechariah (The Vermilion Ace) and Moses' deaths to force the distortion phenomenon on Ciel through Rapture, directly causing the Echo of the City incident.