Sazed is a Terrisman, Steward to Lord Renoux and a Keeper of Terris. Sazed is a user of Feruchemy, scholar of religions, and rebel amongst his order. Sazed, like other Terrisman stewards, is a eunuch to prevent breeding and the spread of Feruchemy's gene.
History
Sazed is a scholar, and studies religion and other ideals to teach when the Lord Ruler falls and the people are free. During the second book he falls in love with fellow Keeper Tindwyl. After her death during the Siege of Luthadel, Sazed begins to doubt his religions and usefulness in life. All throughout the third book Sazed tries to rediscover his religion, eventually discovering right before Ruin attacks the Kandra Homeland.
At the end of this battle, Sazed absorbs the power of Preservation and Ruin, becoming "God" and restoring the world through use of knowledge recorded in his copperminds. He makes Spook a Mistborn.