Dimah Tchakova was a cadet at Corbulo Academy of Military Science. Dimah was born and raised on her home world of Reach. Her family is from an extensive military background with her mother being secretary of FLEETCOM and her father, a high-ranking intelligence officer in the UNSC Navy. Like many colonists from Reach, Tchakova is of Eastern European descent. Dimah develops a close relationship with classmate JJ Chen, helping him through the unfamiliar world of military life.
Halo 4: Forward Unto DawnEdit
Dimah is first seen with the rest of Hastati Squad after classmate Thomas Lasky cost them their already low combat scores. After JJ Chen expresses his anger towards Thomas about their low combat scores back at their barracks, Dimah tells JJ that talking to Thomas is no use, calling him an "Innie sympathizer" in the process. Later that night Dimah is seen holding a small stuffed animal while her roommate Michael Sullivan is piecing together classified combat footage between UNSC Marines and an unknown enemy. She saw Michael watch another classified clip and promised not to tell.
Dimah is seen in episode three with the rest of Hastati Squad watching the full declassified combat footage that Michael pieced together. They watch as UNSC forces overtake a group of Insurrectionists when later both UNSC and Insurrectionists are fighting together against an unknown enemy. Dimah and the rest of Hastati Squad also get a glimpse of a SPARTAN-II which shows to be Fred-104. At chow hall they debate on who the mysterious UNSC soldiers were. Later that night Dimah is with the rest of Hastati, as well as the entire student body, gathering at the academy orbital lift to be transported to waiting UNSC ships for a full scale evacuation. After watching a large group of Orbital Drop Shock Troopers being dropped into campus, Thomas concludes that the school is under attack. Scared and wanting to leave as fast as possible, Dimah uses her family's position to get on board the last lift. Just after taking off, three SDV-class heavy corvettes appear and shoot down the orbital elevator causing it to collapse. This ultimately results in Dimah's death.
- Halo 4: Forward Unto Dawn (First appearance)