The Osean Marine Corps (OMC) are an elite branch of the Osean Defense Forces. The Marine Corps were deployed on tough missions, including special operations, combined-arms, and amphibious assaults on hostile territories.
During the Circum-Pacific War, the Osean Marines were deployed on high-risk operations in behind Yuktobanian lines. These included the rescue of Osean prisoners of war and later, the rescue of Captain Kei Nagase and a crashed gunship crew in Glubina.
Later on, when the survivors of the Wardog Squadron were taken to the OFS Kestrel stationed at Kirwin Island. On December 9, 2010, both Sea Goblin and Wardog, along with VFA-206 Captain Marcus Snow, rescued Osean President Vincent Harling from Stier Castle. After the liberation of Harling, he turned both the Wardog survivors and Snow into his personal aerial squadron called Razgriz Squadron, along with the Kestrel crew and Sea Goblin, under his command.
Sea Goblin ultimately proved crucial in ending the war; they transported Harling and Yuktobanian Prime Minister Seryozha Viktrovich Nikanor to Oured, where the two of them hold a joint televised conference as they retook command of their governments. They also exposed the Belkan hard-line faction, the Grey Men.
On June 6, 2019, during the Lighthouse War, Sea Golbin was once again tasked with rescuing Vincent Harling, who was no longer the President of Osea. After Trigger destroyed the anti-air defenses, Sea Goblin landed at the International Space Elevator, where they were ambushed and ultimately killed.
On September 16, the Osean Marine Corps' Basilisk Team participated in Operation Werewolf, where they assisted the Long Range Strategic Strike Group capture an airbase in Cape Rainy. After successfully capturing the base, Basilisk conducted the landing guidance for Osean aircraft.
- Masato Kanno's Twitter reply to question regarding Osean Marines' official name. Published March 12, 2020. Retrieved March 23, 2020.
- Mission 14: "Ice Cage", Ace Combat 5: The Unsung War.
- Mission 15: "White Noise", Ace Combat 5: The Unsung War.
- Mission 20: "Ancient Walls", Ace Combat 5: The Unsung War.
- Mission 25: "Heartbreak One", Ace Combat 5: The Unsung War.
- Mission 04: "Rescue", Ace Combat 7: Skies Unknown.
- Mission 14: "Cape Rainy Assault", Ace Combat 7: Skies Unknown.