Character Arc
Tyrion Lannister is the youngest son of Tywin Lannister, head of the wealthiest family in Westeros. Born a dwarf, Tyrion has been despised by his father and sister Cersei his entire life. He compensates for his physical stature with a razor-sharp intellect, cutting wit, and a voracious appetite for books, wine, and the company of others. As he tells Jon Snow in the very first episode: "Never forget what you are. The rest of the world will not. Wear it like armor, and it can never be used to hurt you."
Tyrion proves himself a capable political operator, serving as Hand of the King to Joffrey and masterminding the defense of King's Landing during the Battle of the Blackwater. Despite saving the city, he receives no credit — his father Tywin takes command and his nephew Joffrey mocks his disfiguring battle wounds. When Tyrion is falsely accused of Joffrey's murder and condemned to death, he demands trial by combat, and his champion Oberyn Martell is killed by the Mountain.
The pivotal moment of Tyrion's arc comes when he murders his father Tywin with a crossbow after discovering Tywin's betrayal regarding Shae. Fleeing across the Narrow Sea, Tyrion finds new purpose as advisor to Daenerys Targaryen, becoming her Hand of the Queen. He believes in her capacity to be a just ruler and works tirelessly to temper her more destructive impulses.
Tyrion's faith in Daenerys is shattered when she burns King's Landing. He resigns as her Hand and is imprisoned. In the finale, he convinces Jon to kill Daenerys and then persuades the lords of Westeros to name Bran Stark king, with Tyrion serving as Hand of the King once more — a role he accepts as penance for his failures.