Codex Gamicus
Developer(s) Introversion Software
Publisher(s) Publisher Missing
Designer Chris Delay
Gary Chambers
Engine Engine Missing
status Status Missing
Release date September 29, 2006 (Steam)

June 15, 2007 (UK Retail)
April 15, 2007 (United States)
April 19, 2007 (Macintosh)
Q3, 2009 (Nintendo DS)[1]

Genre Real-time strategy
Mode(s) Multiplayer
Age rating(s) Ratings Missing
Platform(s) Windows
Mac OS X
Nintendo DS
Arcade system Arcade System Missing
Media Media Missing
Input Keyboard, Mouse
Requirements Pentium III Processor, 600 MHz, 128 MiB RAM, GeForce2 video card, 60 MiB HD, internet connection (for multiplayer games)
Credits | Soundtrack | Codes | Walkthrough

DEFCON is a real-time strategy game created by independent British game developer Introversion Software, developers of Darwinia, Multiwinia, and Uplink. The gameplay is reminiscent of the "big boards" that visually represented thermonuclear war in the films Dr. Strangelove, Fail-Safe, and especially WarGames.

The game has been available by download since September, 2006 through Introversion's webstore and Steam. In the UK it was released for the high street shops on June 15, 2007 and for a limited period includes the developer's first game Uplink. On April 5, 2007, U.S. publisher Encore announced they would be publishing the game in the United States, and had ordered an initial 50,000 copies of the game for retail.[2]



In DEFCON, players are given a 1980s vector graphics computer-themed world map, a varied arsenal of nuclear and conventional weaponry, and a primary objective: destroy as much of the enemy's population as possible while having as little of one's own population destroyed as possible. A typical game will see civilian casualties numbering in the millions (megadeaths) while players try their hand at annihilating their opponents. Attacking is a very risky strategy that leaves oneself wide open to counterattack.

In most games, all sides take heavy losses, but the player with the highest score wins. Players' scores are determined according to one of three schemes: Default (gain 2 points for 1 megadeath caused, lose 1 point for 1 megadeath suffered), Survivor (gain 1 point per million survivors in your territory) or Genocide (gain 1 point for each megadeath caused); though functionally identical in a one-on-one conflict, each scoring scheme suggests large differences in strategy in larger multiplayer conflicts.

The Default scoring scheme is an average game where players can freely choose their own strategies and where the largest amount of variability could possibly be seen. It is a friendly balance of defense and offense, and is generally the most widely played mode online. The Survivor scoring system tends to have players be more defensive and tactful in their exploits, as there are no points for kills, and sometimes drawing out games to many hours. Nuclear weapons are typically employed as last resorts, as it is possible to win the match using only the initial naval units. The Genocide scoring system is most akin to a "sudden death" match. All players tend to launch nukes very early on in the round, causing fast games with high death counts, and very limited strategies.

Gameplay time can be varied by configuring the speed at which events progress from real-time (1 second in-game:1 second out-of-game) to 20* real-time. Most games last 30 to 40 minutes while real-time gameplay can last more than eight hours, depending on the mode of scoring. There is also an "Office" mode of play in which the game is permanently real-timed and can be minimised to run in the background of other computer activities, allowing the player to check in only when important events take place, and only for so long as it is necessary to modify the standing orders of each of the player's assets.

The game offers six territories that may be selected by a player or assigned to an AI opponent. These include:

All territories have by default a population of 100 million.

File:Defcon zoomed.jpg

An attack on Mexico.

Pacing and DEFCON levels[]

DEFCON is a streamlined Real-time strategy game, with no unit production, resource collection, or technology tree upgrades. Players choose and position their forces at the beginning of the game. A countdown system prevents games from disintegrating prematurely. Gameplay begins at alert level DEFCON 5 and counts down to DEFCON 1 (the highest alert level). Each upgrade in alert level brings more possibilities.

Status Reached
5 No hostile action. Players may place units and fleets and units can move into international waters. Game start
4 No hostile action. Radar coverage will provide information on units within range. Players may continue to place units and fleets and move units into international waters. 6 min.
3 Conventional naval and airborne combat is authorized. Units and fleets can no longer be placed. 12 min.

No effective change from DEFCON 3. This is the final stage before nuclear weapons are available.

20 min.
1 The use of nuclear weapons is authorized. Intercontinental ballistic missiles, submarine medium-range ballistic missiles, and bomber short-range ballistic missiles are available. 30 min.

Once DEFCON 1 is reached, the game proceeds until a certain percentage (80% by default) of the total number of nuclear missiles available to all players have been launched or destroyed. Once this occurs, a victory countdown begins (45 game minutes by default) and the final score is announced when this countdown runs out.

Multiplayer and alliances[]

File:Defcon world overview.jpg

A six-player battle.

A DEFCON game can host up to six human or AI players. Alliances can be formed, broken, or renegotiated at will with human players. Alliances with CPU controlled players can only be set at the start of the game. Allied players share radar coverage and line of sight, but there is no allied victory and there is only one winner. This means that almost all alliances are broken by the end of the game. Lead designer Chris Delay explains:

We've seen alliance members shooting overhead friendly planes down because they believed the planes were scouting the area for targets in preparation for a strike. This results in arguments in the chat channels, followed by skirmishes at sea, followed by retaliation, before finally the whole alliance collapses and everyone starts nuking the hell out of each other. It's awesome.

The chat system features a public channel, in which all players may communicate, as well as channels private to specific alliances, and direct player-to-player private messaging.

Multiplayer modes[]

Diplomacy mode[]

In a game with the diplomacy option, all players start as members of a single alliance, and attempt to stay on top as the alliance disintegrates. Score is determined not by enemy population killed, but by which territory has the highest percentage of survivors at the end of the game.

Office mode[]

In Office mode, the game runs in real time and cannot be sped up. The game can be quickly forced to the background making the computer available for other use, or simply to make it appear the gamer is actually working. While the game continues to run in the background, a system tray icon will notify the gamer of certain events as they occur. The office mode hotkey, sometimes referred to as the boss key, is activated by striking the escape key twice in rapid succession. A game in office mode lasts no more than six hours. The boss key is available in all game modes, but it is designed for this mode in particular.


DEFCON uses a real-time line of sight system common to traditional RTS games, where only enemy units within radar coverage may be seen. However, a nuclear missile launch from a silo or submarine is automatically detected by all players (though the missile itself is not, and must be detected by radar), which reveals the location of the unit launching the missile. A nuclear missile launch from a bomber, however, does not reveal the location of the bomber.

Most units have several operating modes for different functions, and require several minutes to switch modes. For instance, ordering a missile silo to switch from offensive launches to missile defense will leave it inoperative while it switches.

Ground units[]

Ground installations are immobile, and can be destroyed by nuclear attack.

  • Radar dishes provide broad radar coverage (though most units have some radar capability), but can be destroyed by a single nuke. They enhance other defense installations; for instance, a missile silo's firing range far outstrips its radar range. A radar dish can be destroyed if a fighter or bomber runs out of fuel or is shot down directly over it, even before DEFCON 1.
  • Missile silos have two modes: launching nuclear missiles or shooting down incoming missiles and planes. In the attack mode, a silo has ten ICBMs that may be fired at any target in the world, though doing so alerts all players and reveals the silo's position. On defense, a silo automatically fires surface-to-air missiles effective against enemy planes and missiles – however, the limited rate of fire means the silos can be overwhelmed by many incoming missiles. Unlike most units, silos are hardened against nuclear strikes, taking three hits to destroy, although each strike eliminates half (rounded down) of the silo's nuke stockpile.
  • Airbases house bombers and fighters plus a complement of five spare SRBMs to reload bombers that have launched their missiles. They launch planes and provide a landing point for orphaned aircraft, and also build new fighters automatically throughout the game. Airbases take two hits to destroy; on the first hit, half of the airbase's currently landed aircraft and missiles are destroyed.


Naval units are organized into fleets of up to six ships which move and fight together. Fleets must be placed in territorial waters at the beginning of a game. Ships may move through the ocean, albeit slowly.

File:Defcon Pacific attack.jpg

A mid-Pacific battle.

  • Carriers act as mobile airfields, scrambling fighters and nuke-equipped bombers. They are also the most powerful anti-submarine warfare escorts, armed with sonar and depth charges that quickly sink nearby subs. With no surface guns, they are helpless without their complement of planes.
  • Battleships are tough and carry powerful guns effective against surface fleets and aircraft. They are vulnerable to sub and bomber attacks, so are safer with carrier escorts.
  • Submarines carry torpedoes and an arsenal of five nukes. Sub attacks are dangerous against enemy ships, though subs are easily killed by carriers. Subs are invisible to radar but carry no radar of their own; they may use active sonar to pursue other naval units, at the risk of exposing their position. Their real power comes from their missiles, which can devastate coastal cities, or quickly hit defenses before a full-scale strike. Subs must surface to fire nukes, leaving them open to counterattack before they can fire all their missiles; the launch also alerts all players to the sub's location.


Aircraft are launched from other ground and sea units. Typically they operate autonomously after launch, but bombers and fighters can also be controlled while airborne.

  • Fighters are light and fast, making them good at reconnaissance and interception. They are most effective against other aircraft, though they can attack ships as well. They have a fairly short range, forcing them to return to a base or crash for lack of fuel.
  • Bombers carry a single SRBM missile that may be fired at a nearby target. Bombers have a long range to deliver this payload, but are vulnerable during the trip. Unlike silo- and submarine-based nukes, firing the missile does not alert everyone to the launch, making it a stealthier option. They also have a conventional attack that does heavy damage to ships.


  • Missiles deliver a devastating payload. A direct hit on a city will kill half of the current living civilians. Between one and three hits are required on the hardened buildings that players place to destroy them. Missiles can only be shot down by enemy silos in defense mode, which have a small random chance of hitting the missile with any given shot — a hit will cause a limited detonation in the missile, yielding minor casualties if a city is directly beneath, or damaging or destroying a facility if one is below. Once launched from a silo (ICBM), submarine (called MRBM, although technically an SLBM), or bomber (called SRBM, although technically an ALBM), missiles cannot be retargeted, though they can be disarmed in mid-flight. Missiles can also target sea-based units and will destroy any aircraft caught in their blast radius.


Review scores
Publication Score
Bovine Conspiracy 9/10
Mansized 5/5
Entity Award
PC Gamer Top 100 PC Games July 2008 (# 59)
Way of The Rodent Best Involuntary Yelp
Way of The Rodent Best Sound

Reviews of DEFCON have been mostly positive with a Game Rankings average score of 83.3%,[3] and a Metacritic average score of 84/100.[4] said of Defcon, "this just may be the finest piece of "budgetware" ever produced, with every bit as much to offer strategywise as RTS games three times its cost.", praising the "elementary" interface and calling the strategic depth "enormous." 1UP also praised the visuals, calling it "one of the best-looking PC games all year."[5] Edge said Defcon was "worth it for the presentation alone".[6] Eurogamer commented that it was "the least ambitious of Introversion's games in terms of design", and "its limitations are ones of the game's basic scope.", while praising Defcon as "as pure and direct a game as its inspiration."[7]

Common complaints[]

Bots are typically notable for their immediate usage of nukes. During online play, if a player leaves during a game, a CPU player will take their place. This usually results in the computer launching all of its remaining nukes as soon as possible, foregoing any conventional strategy.[8] In newer versions of the game, bots utilize a different strategy and will not launch until the game has been in DEFCON 1 for a fair amount of time, or more commonly when another player launches. Bots also started using more strategy in which weapons they use, SLBMs from submarines and SRBMs from bombers are often used before a silo-based ICBM is used, to avoid compromising the position of the silo. Bots are still not capable of some strategies commonly used by human players, such as using nuclear weapons to destroy the enemy's navy.

Another is the AI's inability to vote on Alliances. If the game starts with AI players, any alliances with them must be broken by the Human player leaving. If there are two CPUs in an alliance, there is no way to separate them.

See also[]

  • WarGames (game)
  • Nuclear War (computer game)


  1. DEFCON for DS! (2009-04-20). Retrieved on 2009-04-29
  2. Defcon Bombing US Retail. Next Generation (2007-04-05). Retrieved on 2010-04-01
  3. DEFCON: Everybody Dies Reviews. Game Rankings. Retrieved on 2008-08-15
  4. DEFCON: Everybody Dies (pc: 2006): Reviews. Metacritic. Retrieved on 2008-08-15
  5. Peckham, Matt (2006-10-07). "DEFCON Review". 1UP. Retrieved 2008-11-22. 
  6. Edge magazine, November 2006, p.90
  7. Gillen, Kieron (2006-10-02). "Defcon Review". Eurogamer. Retrieved 2008-11-22. 
  8. Most desired patch upgrade?. Introversion software. Retrieved on 2008-08-15

External links[]

Template:Introversion Software Template:Ambrosia Software Template:War Games fr:Defcon (jeu vidéo) fi:DEFCON (peli) sv:DEFCON (datorspel)