Canonized

Needs Legends of the Dead, and the recipe is precise: unlock the THIRD Heroic Bloodline dynasty legacy, then create a Holy-type legend with YOURSELF as the protagonist, promote it to Mythical quality and complete it - that combination grants the Venerated Ancestor trait, i.e. sainthood, to the protagonist. The wiki stresses the protagonist choice because doing it for someone else's glory doesn't pop it for you. The cheap-legend game rules (Legend Cost Very Low, Spread Chance Very High) keep the promotion phase painless. Legendary! comes free.