Chasm: The Rift (DOS) is a 3D first-person shooter. As a Marine, the player has been sent inside a power plant to investigate the loss of power at the plant. They later discover that a group of monsters known as the Timestrikers are using the power to create ruptures in time that allow them to invade the Earth in three different time periods: present day, ancient Egypt, and medieval times. Timestrikers that have invaded the present day are also taking control of a nuclear plant in order to detonate a nuke that will destroy nearly all life on Earth.
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