Story

Set in 2020, Crysis' plot follows Lieutenant Jake Dunn—codenamed "Nomad"—a United States Army Delta Force operator. As Crysis begins, an American team of archaeologists are taken captive by the North Korean Army, just as they were making an important discovery in the South China Sea. The United States responds by deploying a team of Delta Force Soldiers,—supported by the USS Constitution—who take part in the fighting between the United States and North Korea. Soon, though, it becomes apparent that the North Koreans have large military installations. During this phase of the game, the setting is a tropical environment, similar to that in Far Cry, Crytek's previous game.

At the end of the first section, the mountain at the center of the island begins to crumble revealing a two-kilometer high alien structure beneath the surface, out of which aliens begin attacking both the US Military and North Koreans. Nomad enters the alien ship in this section and begins to explore the weightless environment, retrieving valuable information about the alien invaders, who periodically attack him. On exiting, the ship xenoforms the area around the island by creating an ice sphere, killing every living thing within it. The final section of the game takes place on the USS Constitution.