Another single-player shooter I've played is Half-Life 2. It was released back in 2004 for PlayStation, Xbox, and PC. It has a Linux and Mac release, and was rated M (for Mature).
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{"name": "Half-Life 2", "release_year": "2004", "esrb": "M (for Mature)", "genres": "shooter", "has_multiplayer": "no", "platforms": "PlayStation, Xbox, PC", "has_linux_release": "yes", "has_mac_release": "yes", "intention": "inform"}
assistant