Echo/419: Cast of Characters

	Captain Keyes Captain Jacob Keyes commands respect as a keen strategist and inspirational leader of his men. He became a minor hero early in his career, when he led a small group of security troops against a Covenant ambush of the colony ship Meriwether Lewis and held them off long enough for the ship to escape. Prior to that, Keyes assisted Dr. Catherine Halsey in the selection of candidates for the SPARTAN II program due to his excellent ability to keep secrets. Because of his background with the SPARTANs and Halsey, he was selected to command the Pillar of Autumn and its secret cargo.
	Cortana Cortana is a highly advanced artificial intelligence based on the brain of Dr. Catherine Halsey. She was specially designed to complement the MJOLNIR Mark V battlesuit, but she is also capable of taking control of a starship. Cortana is unique in that her dynamic memory-processor has no constraints on its programming, leaving her free to think about whatever she wants instead of limiting her to a specific use, although it does limit her useful lifespan. This gives her a unique, almost human personality and character. Cortana was assigned to assist the Master Chief after Captain Keyes ordered the abandoning of the Pillar of Autumn.
	The Master Chief The Master Chief believes himself to be the last survivor of Project: SPARTAN II, which was undertaken by the human military nearly forty years ago. Under Dr. Halsey, the Master Chief and seventy-five other kidnapped children were trained by the best and augmented with a ceramic-plated skeletal structure, enhanced optical nerves, and accelerated reflexes. Shortly after first contact with the Covenant, the SPARTANs were equipped with new MJOLNIR Mark IV battle armor, which directly interprets neural feed to the muscles into motion and thus increases reflexes almost fivefold. The MJOLNIR system was recently upgraded to Mark V, which supports a starship-grade AI such as Cortana and full-body defensive shielding. The other SPARTANs were presumed killed at the battle of Reach. However, some of them were later rescued by the Master Chief and a squad of survivors from Halo (see Halo: First Strike).
	343 Guilty Spark Very little is known about 343 Guilty Spark's origin. He is an artificial intelligence in a glowing blue, self-repairing matrix which is capable of hovering, teleporting and manipulating objects and control panels. He presented himself to the Master Chief after the release of the Flood and explained himself as being Halo's Monitor, whose function is to prevent the Flood from spreading. He apparently mistook the Master Chief for someone called the Reclaimer, who wears similar armor. When the Master Chief and Cortana attempted to stop 343 Guilty Spark from activating Halo's weapon and destroying all life in the galaxy, he turned on them and attempted to hinder their progress through the deployment of armed Sentinel drones.