From Halopedia, the Halo wiki
Michael Baird was born on Earth in Scotland. He often referred to the cold weather he used to enjoy in his childhood. Moments before his death, he remembered how he used to fall on his back and make snow angels when he was a child.
Aboard the UNSC The Heart of Midlothian, Baird received treatment for a form of cancer, a now archaic and easily treatable disease. The procedure was supposed to last only an hour or so, and Baird, who didn't want to miss a jump with his squad, was appeased by Mo Ye, the ship's "smart" AI construct, who said he should be up and ready to jump before they would leave. Baird was actually knocked out for twenty-three hours, and during that time, the Heart of Midlothian, was boarded by a Special Operations Covenant boarding party.
The boarding party
As Mo Ye told Baird about the events that occurred while he was unconscious, he asked why she couldn't just self-destruct, as per the Cole Protocol. She told Baird that this boarding party was unlike any other, as they systematically destroyed Mo Ye's systems to prevent her from self-destructing. She also revealed that they had brought aboard a never before encountered Covenant species. In order for Mo Ye to start the self-destruct sequence, Baird had to travel to the control room and manually boot her systems. She was able to tell him this because she had left a small piece of her coding behind to watch over Baird's procedure.
Armed with only a fire extinguisher, Baird set out for the control room, but encountered a small group of Covenant, consisting of four Unggoy, two Kig-Yar, and one Sangheili. He snapped the first Kig-Yar's neck by smashing down on its head with his fire extinguisher. He then used the fallen Kig-Yar's Covenant carbine to take out the next. As the Unggoy began to disperse in fear, one accidentally ran into him. As they looked at each other, Baird noticed an energy sword running through the cowering Unggoy and himself. He looked up and noticed the leading Sangheili had run him through with his energy sword. As the Sangheili pulled away, the Unggoy fell dead and Baird was knocked unconscious.
Baird was awoken again by Mo Ye, who gave him four medicines, one that was known to be used by Insurrectionists fighting Spartans. It was known as a Rumbledrug, slowly destroying the body, but making it totally impervious to pain and damage. Using these drugs, Baird made his way to the control room, where he encountered more of the boarding party, including the leader, who donned a decorative headdress. Baird dropped his weapons and said he would give them the coordinates of Earth if they let him escape. As they begun to raise their weapons at him, the Sangheili roared at them to stop and communicated with the Huragok onboard. The Sangheili then agreed to let Baird do what he had to do.
Baird reactivated Mo Ye, but instead of giving the boarding party the coordinates, he removed the AI's safety protocols, allowing her to destroy the ship. Baird then punched the Sangheili as hard as he could, breaking his hand and the Sangheili's two left mandibles. He began to taunt the alien, but the Sangheili recovered and beheaded him with his energy sword. As the boarding party left, the Sangheili and Mo Ye made eye contact. When they did, Mo Ye begun counting, but then said "I'm kidding. There's no need for any countdown whatsoever." She proceeded to self-destruct, leaving absolutely nothing but the midnight of space.
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