Phobos has always been a hotly contested area. Skirmishes between the tireless Grineer and Corpus factions occur in orbit and on the Martian moon surface. Unanswered questions about this natural satellite still remain, as all research is endlessly delayed by war.
The sprawling ranks of the Grineer empire are formed of rotting hordes of simpleton clones, bent on consuming everything that remains of the solar system. They live short, violent lives, much of it an inheritance of the genetic stunting by their former Orokin masters.
Weapons research and manufacturing is a large component of Corpus industry. Their designs are clean and precisely engineered, and they are the largest supplier of energy-based weapons in the solar system. These cunning profiteers prefer to avoid conflict in times of war, dealing arms indiscriminately to any side that can afford the price.