Who is the main character of the game Half-Life: Opposing Force?

The main character of the game "Half-Life: Opposing Force" is Adrian Shephard. As a member of the United States Marine Corps, he is deployed to the Black Mesa Research Facility to contain an alien invasion. Throughout the game, players control Shephard as he navigates through dangerous environments, battles aliens and human enemies, and uncovers the secrets of the facility. Shephard's story offers a unique perspective on the events of the original "Half-Life" game, showcasing his resilience, bravery, and determination to survive against all odds.