Quick Summary
Deicida is a protector because protection is the only shape his penance can still take. Once the consecrated Sentinel of the Argent Temple, he accidentally slew the god he was sworn to defend when a Balor's spiteful teleport turned his perfect killing thrust aside. He walks now with ruined eyes that still see too much: ghosts, shame, and the fragile threads of lives he no longer believes he deserves to guard.
Backstory
Before he took the cursed name Deicida, he was the Sentinel: last bastion of the Argent Temple, guardian of an alabaster-and-gold spire where his god of light and law made a home among mortals. His soul had been shaped around that duty. Clad in the Plate of Oaths and bearing Caelestis, the God-Blade, he stood as the hand between divinity and the dark.
When the Abyss tore open above the temple, he held the nave for hours against the demonic tide. At the battle's apex, a Balor breached the inner sanctum. The Sentinel poured faith, fury, and every remaining breath into a single perfect thrust meant for the demon's heart. The Balor vanished ten feet aside. Caelestis found the god instead.
The temple did not explode. It stopped. Light, hymn, battle, and purpose collapsed into a silence that left only the dead blade in his hand and the eyes of the survivors on him. He burned his own sight away as penance, but the universe denied him darkness. Now he sees through the spectral haze of that failure and searches for the impossible: a way to resurrect the god he ended, not for absolution, but to earn the mercy of a final night.