Early Life and Mercenary Career
The youngest surviving child of Captain-General Janos Marik and his favorite, Kristen was a stubborn woman in her youth. She set creating a mercenary unit as her goal and thus making a name for herself. At age twenty, she changed her last name to "Markus" and signed up with the mercenary unit Langendorf's Lancers as a tech. The mercenaries soon discovered who she really was despite her name change. However, through her own merit, she was awarded a captured Steiner Hunchback. Her skills piloting the 'Mech rose as she claimed 3 kills by 3025.
She seldom visited her father during this time, having come to odds with him for taking a lover, Bronwen Rafsani, who was barely older than she was.
Kristen received a sizable fortune from her father's will. She became Duchess of Augustine, though she had little use for the title. Kristen put her inheritance to good use. She took a number of warriors from the Lagendorf's Lancers to build the core of her new mercenary unit, creating the regiment Kristen's Krushers in 3037. She then based the mercenary unit on Claybrooke, getting her first contract from the Free Worlds League as a garrison force. Her unit moved on to contracts for both the Federated Suns and Lyran Alliance, slowly achieving her dream of becoming an Inner Sphere recognized unit.
FedCom Civil War
By 3062, Kristen and the Krushers were under contract with the Lyran Alliance, stationed on the world of Coventry. In December, conflict erupted between the Coventry CPM and the Alliance Jaegers with the death of Arthur Steiner-Davion. The commander of the Jaegers, Jason Walker, ordered the Krushers to attack full on into Port Lawrence's Coventry Militia Academy, taking heavy damage. Kristen protested the brutality of the Alliance's assault. Walker took this as an opportunity to attack the Krushers, citing them for "evidence of complicity with the traitors".
Kristen's son, Major Ana Marik, commander of the Third Battalion, died holding off Jaeger forces long enough for his men to escape. Kristen led her people to their DropShips and left the planet, communicating that the Jaeger attack voided their contract with the Lyran Alliance.
In March 3063, she led the Krushers in a raid against Gallery for supplies. However, the world's ruler, Nondi Steiner was not pleased with this. She labelled the mercenary unit hostile and ordered her forces to take measures against them when they could.
Kristen had led her people to Arcadia, where her unit faced an impressive Aerospace force, led by the Mjolnir Class Battlecruiser, LAS Yggdrasill. The enemy aerospace power forced her to scatter landing sites on Arcadia, where the split up mercenary unit faced the 2nd Donegal Guards. Kristen led her force in a desperate fight for survival, leaving only 2 operational companies by April.
However, the balance of power changed as the 6th Marik Militia arrived on planet under escort by a Thera-Class Supercarrier battlegroup clearing the skies of hostiles. In the last hours of fighting with the 2nd Donegal, Kristen fell in battle. 
- Kristen was known for her stubbornness, her determination to go it alone without using her family name for gain. She resembled her father and was considered to be homely.
- She was a noted Hunchback pilot while signed up with the Langendorf Lancers.
- Kristen had three children with Jiri Rousset; Ana, Janos and Alys.
- House Marik (The Free Worlds League), p. 141 - "Kristen Marik character profile"
- FedCom Civil War, pp. 38-41 - "Eagle's Flight" - "Kristen Marik killed in last hours of battle on Arcadia".
- Mercenaries Supplemental Update, p. 81 - "The Krushers unit profile"
- 20 Year Update, p. 93 - "Kristen Marik's brief profile" - "Summary of events since 3025".