Crysis Warhead is a first-person shooter video game developed by Crytek Budapest and published by Electronic Arts.

The story follows Sergeant Michael "Psycho" Sykes, an ally of Crysis protagonist Nomad, as he faces his own trials and challenges on the other side of the island during the time period of the first game.

Crytek has made numerous changes to the multiplayer gameplay including tighter vehicle controls, weapon rebalancing, and Nanosuit alterations.

British SAS Sergeant Michael "Psycho" Sykes is a member of the Raptor Team, a squad of mostly U.S. soldiers outfitted with advanced nanotechnology.

Leaving the shore, he joins a Marine vehicle convoy driving through the jungle, and defends it as it is attacked by North Korean soldiers.

Psycho awakes and goes to find a better position for the surviving Marines, but gets attacked by an EMP blast from a container being lifted away by a North Korean helicopter.

As the mission progresses, Psycho is reunited with friend U.S. Navy fighter pilot Sean O'Neill who was originally going to have Nomad's spot on Raptor Team.

Emerging above ground, Psycho fights off both North Korean soldiers and aliens trying to reclaim the container, while O'Neill assists him.

Psycho is ordered to destroy the container if he cannot capture it, and the train is stopped on a bridge which is rigged with explosives in case he needs to do so.

He takes out his rage on an injured nanosuited North Korean soldier he pulled off the bridge with him, and drowns him in the river.

Struck with grief for not saving the life of the Marine, Psycho has an emotional breakdown, but regains his composure in order to finish his mission.

O'Neill returns in a VTOL, and assists Psycho in destroying an upgraded Exosuit walker by guiding him to a crashed U.S. Air Force cargo plane, which was transporting a powerful experimental weapon, the PAX (Plasma Accumulator Cannon), which allows him to fight off the initial wave of attackers.

These clips show brief glimpses into how O'Neill failed his evaluation test probably causing the death of some other squad mate as can be guessed by the fact that Psycho says "Man Down".

The dead squad mate might be the nephew of Dominic H. Lockhart, commander of the Crynet Enforcement & Local Logistics (CELL).

[11] Crysis Warhead uses a modified version of the digital rights management software SecuROM as copy prevention, which requires authentication on installation and when online access is used.

Indeed, some reviewers did not see any significant performance improvement with Warhead compared with Crysis, stating that only high-end GPUs could handle the game comfortably at decent frame rates.