Zeke
Jaeger

Zeke was built, not raised. His parents ran the Eldian Restorationists in Liberio, and they drilled forbidden history into their son and groomed him for the Warrior program as their weapon inside Marley. The plan was that Zeke would carry the movement; nobody asked what Zeke wanted. The only adult who treated him like a child was Tom Xaver, the Beast Titan's holder, who played catch with him after training. On Xaver's advice, Zeke turned his own parents in to Marley Public Security, saving his grandparents and himself and sending Grisha to a Titan's fate on Paradis.

He inherited Xaver's Beast Titan and became Marley's war chief, the strongest holder the Titan had ever had thanks to blood no one in Marley knew about: his mother was Dina Fritz, last royal on the continent. His spinal fluid could turn anyone who ingested it into a Titan at his scream, and his victims obeyed him. Ragako was his work. So were the boulders that annihilated the Scout charge at Shiganshina, where Erwin died and Levi tore him out of his Titan and nearly finished him. He came away from that battle with a scar and a permanent fear of Levi that later proved justified twice over.

His grand plan came from Xaver's research and his own conclusion that Eldians were better off unborn: use the Founding Titan to sterilize every Subject of Ymir and let the race end quietly. He smuggled his spinal fluid into Paradis in wine, screamed Levi's escort into Titans, and blew himself in half with a Thunder Spear rather than stay captured, all to reach the Paths with Eren. There he learned he had been the key to someone else's plan, and that his little brother had lied to him from the first handshake. It was Armin, swallowed into the Paths near the end, who reached him, with a memory about playing catch and the worth of things that serve no purpose. Zeke gave the alliance the wind it needed by raising the dead holders of the Nine, stuck his head out to remark that it was a nice day, and let Levi take it.