The C'tan Shards are all that remains of the star-gods who once devoured suns and reshaped galaxies. In an age beyond memory the Necrons worshipped these entities of living energy, until the day the deathless dynasties turned upon their masters and shattered them into countless splinters. Each shard retains a sliver of the whole's godlike power, and a fraction of its boundless malice.
Bound into necrodermis prisons and leashed by the technologies of their former slaves, the shards are now weapons in the arsenals of the Necron dynasties. A single splinter can boil oceans, unmake matter with a gesture, or drink the life from an army. Yet even bound, a C'tan Shard is never truly tamed. It remembers what it was, and it schemes across the slow centuries to slip its chains and gorge upon reality once more.
To unleash a shard is to gamble with catastrophe. The Necron lords who command them do so warily, knowing that the fragment's obedience is a fiction maintained only by ancient wards and the constant vigilance of the crypteks. Where the Nightbringer or the Deceiver walk in splintered form, whole worlds learn to fear the memory of gods, and even the youngest races feel an instinctive dread older than their species. The shards are hunger given shape, and they wait.