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"The biggest embarrassment has been Black Mesa facility, but I think that's finally taken care of itself... quite so."
The G-Man[src]

The Mark IV Thermonuclear Device, nicknamed "The Package", is a thermonuclear warhead stolen by the Black Ops, and used to destroy the Black Mesa Research Facility.


G-Man bomb activate

The G-Man reactivating the bomb.

The bomb is first introduced in Opposing Force's fifth chapter, Friendly Fire, where it can be seen in the back of a truck, guarded by two Black Ops assassins, and near the rocket from which it was removed, in an Ordinance Storage Facility connected to Sector E Materials Transport.

Later in the game, in the thirteenth chapter, "The Package", Shephard discovers two other Black Ops assassins setting up the bomb in an underground parking lot under the large Ordinance Storage Facility and connected to Sector E Materials Transport. After killing the assassins, he deactivates it. Afterwards, he proceeds to a nearby room with a view on the truck, and witnesses the G-Man reactivating it. He cannot return to the truck, making the destruction of Black Mesa inevitable.

The bomb explodes when Shephard is detained by the G-Man aboard an Osprey at the end of the game, when a white flash covers the screen while the G-Man makes a slight pause in his monologue.


The following instructions are written inside the bomb's lid:


This device carries a GRADE C plutonium control detonator.
With this device an approximate safe distance of
55 kilometers is recommended.

Indispose the gravatronic rev limiter to 11.
Rotate red knob to the on position.
Press button labeled B.

Behind the scenes

Although subsequent games tend to disregard the Gearbox expansions' storyline, series' writer Marc Laidlaw has confirmed that the destruction of the Black Mesa Research Facility at the end of Opposing Force is canon.[1]


  • In the chapter Friendly Fire, the bomb only appears as a rough brush, while it is a detailed model in the chapter "The Package".
  • The warhead's lid has a set of instructions, one of them humorously reads: "Indispose the gravatronic rev limiter to 11." This being a reference to the film 'Spinal Tap' and the famous amp scene, the joke here being that a nuclear bomb's damage lever doesn't end at 10, it unnecessarily goes one higher.
  • The device resembles the American W88 thermonuclear warhead, with the exception of the side mounted control panel which could be a custom modification by the Black Mesa Research Facility on a pre-existing warhead. The control panel could however be apart of an original warhead design, hence the name sharing no connection to any other similarly styled U.S. warhead.


List of appearances


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