From Halopedia, the Halo wiki
Markov was an Orbital Drop Shock Trooper assigned to the UNSC Light Frigate UNSC Midsummer Night. He was a close friend of Second Lieutenant Faison, and when Faison took command of the ODST complement of the Midsummer Night, Markov served as his executive officer.
Markov was part of the squad led by First Lieutenant Canfield, later by Faison. He was onboard the freighter Finnegan's Wake, orbiting Charybdis IX, when the Insurrectionists set off explosives that killed First Lieutenant Canfield and wounded and killed some other ODSTs. When Lieutenant Jacob Keyes ordered him to borrow his armor, which Markov was reluctant to obey. He then escaped the Finnegan's Wake in a cargo container under Keyes' orders. Later on, he was part of the ODST group that pinned Keyes down while Chesnick gave him a tattoo.
When the Midsummer Night escaped the Battle of Charybdis IX, Markov was briefly imprisoned by the Insurrectionists in The Rubble. However, he was freed and took part in the Battle of the Rubble and the Battle of Metisette. After Faison was killed by Zhar, Markov took command of the ODST forces participating in the concurrent battles on Metisette and The Rubble. He spent most of the battles enraged, bloodthirsty to avenge Faison.
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