|Death place||DDI Base airspace|
|Aircraft||A-10 Thunderbolt II|
MiG 1.44 MFI
|Affiliations|| United States Air Force|
- "Perform skillfully, and you'll find yourself amply rewarded by DDI. Fail, and I won't have to fire you. The enemy will take care of that for me."
- — Rainmaker to his pilots
Colonel Frank "Rainmaker" Ostreger is a pilot and engineer and former member of the United States Air Force. He flew with Dagger during the First Gulf War. On one mission, they deviated from their course and wandered into a friendly kill zone. They made it to the airport, and Rainmaker abandoned his wingman to take out a bomber. Their next mission was to defend oil fields from the Republican Guards. In an F-14, he defended Dagger as he refueled. They then took out the command center. Soon after, they were assigned to defend Army Rangers escorting an HVT. As they passed through a village, Rainmaker fired on enemy forces, causing collateral damage. He tried to get Dagger to cover for him. He believed that he had the green-light to engage. Afterward, he was given a choice of going to Fort Leavenworth prison or retirement. He blamed Dagger for his disgrace, and it turned out that Dagger had black-balled him behind the scenes. He then formed the PMC DDI and was very successful. He believed the future was about corporations. He had a diplomatic team which started 16 wars behind the scenes, and designed his own UAVs. In revenge, he sabotaged the plane Curtis Bowman was flying, and he was believed killed on a mission.
In the near future, Dagger's son Arrow went to work for him. In response to DDI's disregard for the rules of war, Arrow left and rejoined the H.A.W.X. squadron. Obsessed with power, Rainmaker convinced the pilot Ringo to defect as a means of evening the score and had him killed while testing drones.
Rainmaker then started a covert war against the H.A.W.X. squadron. His hidden base was eventually destroyed by Arrow and Major Zeal and the two chased after Rainmaker who was in an MFI. He tried firing the Firestorm satellite, and fell into Zeal's trap. He flew into the Firestorm beam and was destroyed. His plans to extort the world with his fleet of UAVs patterned after Arrow then fell apart.
The player takes control of him at one point in his A-10.