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Colonel Teller was an Orbital Drop Shock Trooper during the Human-Covenant War. He was a former Colonial Military Administration soldier whose allegiance to the UNSC was highly suspect. Eric Santiago referred to him as a "Watts loyalist."
Disobeying orders and death
In August 2552 the city of Mount Haven on an unknown colony was invaded by the Covenant, who proceeded to dig downriver of the city in search of Forerunner artifacts. In response the UNSC sent in a Company of ODSTs for a snatch-and-run operation; they would steal the artifacts then retreat from the planet.
However, unbeknownst to the UNSC, a team of ODSTs had their own agenda. The nine ODSTs were all former CMA veterans, and felt that they had given enough to the UNSC cause. Their plan was to break into a bank in the city center, and use a spare Pelican dropship to steal the gold and platinum ingots stored in the bank's vault. They justified their theft by saying that the precious metals were going to be glassed anyway, and therefore they "didn't exist anymore." The team would use the gold to retire.
Their plan hit a snag however when they discovered a schoolteacher and a group of children taking refuge in the bank vault, causing an argument to erupt between the five ODSTs in the vault. Gage Yevgenny wanted to abandon their theft and evacuate the children. Felicia Sanderson was in favor of calling in an extra Pelican. Sita, Dale and Orrin however wanted to abandon the civilians to their deaths. Tempers flared, and the ODSTs turned their weapons on each other; Gage and Felicia against the other three. Dale was shot and killed in the brief shootout; his shots may have wounded Gage or killed Felicia. Teller had accompanied the team to the bank, but was not present for the altercation. He was likely killed when Gage later set off a Shiva nuclear warhead near the city.
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