Atium

Atium, the rarest Allomantic metal in the Mistborn Era 1 trilogy, begins as the godlike Lord Ruler's secret weapon for prescience and immortality, hoarded in his most secure vaults. Its pivotal role escalates in the cataclysmic events of The Hero of Ages, where it proves essential to defeating Ruin by enabling Vin to perceive and shadow his destructive avatar. Ultimately, at the world's end, Atium's complete consumption merges it back into Preservation's power, reshaping Scadrial's magic in the aftermath.