Halo: Combat Evolved (commonly known as Halo or Halo 1) is a first-person shooter (FPS) video game developed by Bungie Studios. The first game of the Halo series, it was released on November 15, 2001 as a launch title for the Xbox gaming system, and is considered the platform's "killer app." With more than five million copies sold worldwide as of November 9, 2005, Microsoft released versions of the game for Microsoft Windows (developed by Gearbox Software) and Mac OS X in 2003, and the surrounding storyline was adapted and elaborated into a series of novels. The game was later released as an Xbox Original for download onto an Xbox 360 HDD.
In Halos twenty-sixth century setting, the player assumes the role of the Master Chief, a cybernetically enhanced "SPARTAN" super-soldier. The player is accompanied by Cortana, an artificial intelligence who occupies the Master Chief's neural interface. Players battle various aliens on foot and in vehicles as they attempt to uncover the secrets of the eponymous Halo, a ring-shaped structure. The game has been called "easy to learn", and has been praised for its "engaging story".
Many game magazines have praised Halo as one of the best and most important games of all time. The game's popularity has led to labels such as "Halo clone" and "Halo killer", applied respectively to games either similar to or anticipated to be better than it. In addition, the game inspired and was used in the fan-created Red vs. Blue video series, which is credited as the "first big success" of machinima — the technique of using real-time 3D engines, often from video games, to create animated films.
The player character is equipped with a damage-absorbing energy shield, in addition to hit points. The shield's charge appears as a blue bar in the upper-right hand corner of the game's heads-up display. When the shield is fully depleted, the player is highly vulnerable, and further damage reduces the character's health level. However, the shield will recharge if no further damage is sustained for a brief period.
Halo's arsenal consists of weapons from science fiction. The game has been praised for giving each weapon a unique purpose, thus making them useful in different scenarios. For example, plasma weapons need time to cool if fired too rapidly, but require no reloading. Instead, players are forced to discard them after depleting their batteries. In contrast, conventional firearms cannot overheat, but require reloading and ammunition. All weapons may be used to bludgeon enemies, which allows a player to silently kill opponents without alerting other nearby enemies. Players may carry only two weapons at once; thus, a strategy is required when using and selecting firearms.
The player can carry up to eight grenades at a time: four fragmentation and four plasma grenades each. Like the game's other weapons, the two types of grenades differ; the fragmentation grenade bounces and detonates quickly, whereas the plasma grenade adheres to targets and takes longer to detonate. A controller button assigned to grenades eliminates the need to holster firearms before throwing.
A secondary enemy is The Flood, a parasitic alien life form that appears in three main variants. Infection Forms, the true form of the Flood, are fragile, but often travel in swarms; they do little damage individually, but the swarms often number in the hundreds. Combat Forms result from humans and Covenant Elites who are infected by Infection Forms, and have hideously deformed bodies. Bloated Carrier Forms serve as incubators for new Infection Forms, and when wounded or near a potential victim, they explode to damage other nearby life forms and to release their spores. Battling the Flood, Covenant and player are the Sentinels, robotic drones designed by an extinct race called the Forerunners. Sentinels lack durability, but use powerful beam weapons and are immune to infection by the Flood.
The artificial intelligence in Halo has been favorably received. Enemies take cover and use suppressive fire and grenades. Some enemies retreat when their superiors are killed. The player is often aided by United Nations Space Command (UNSC) Marines, who offer ground support, such as manning gun turrets or riding shotgun while the player is driving a vehicle.
Although the Xbox version of Halo lacks official support for online multiplayer play, XLink Kai, GameSpy and XBConnect's packet tunnelling software provide unofficial ways around this limitation. The Windows and Macintosh ports of Halo support online matches involving up to 16 players and include multiplayer maps not in the original Xbox release. However, co-operative play was removed from the ports because it would have required large amounts of recoding to implement. On March 15, 2004, Gearbox Software released Halo: Custom Edition for Windows, which enabled players to use custom-made maps and game modifications.
To prepare for a mission to discover the location of the Covenant homeworld by boarding one of its starships, SPARTAN-II soldiers were recalled to Reach for further augmentation. Two days before the mission was to begin, Covenant forces attacked Reach and destroyed the colony. A starship, the Pillar of Autumn, survived the onslaught and initiated a random jump to slip space (similar to hyperspace), hoping to lead the enemy away from Earth.
The titular Halo is an enormous, ring-shaped artificial space habitat/planet, which (according to Bungie Studios) has a diameter of ten thousand kilometers. Halo sits at a Lagrange point between a planet and its moon. Centrifugal force created by the rotation of the station provides the ring's gravity.
Keyes survives the Autumns crash landing, but is captured by the Covenant. In the second and third levels of the game, the Master Chief and Cortana gather human survivors and rescue Captain Keyes, who is imprisoned on the Covenant ship Truth and Reconciliation. Once rescued, Keyes orders the Master Chief to beat the Covenant to Halo's control center and to discover its purpose. The Master Chief and Cortana travel to a map room called the Silent Cartographer, which leads them to the control room. There, Cortana enters the systems and, discovering something urgent, suddenly sends the Master Chief to find Captain Keyes, while she stays behind. While searching for his commander, the Master Chief learns that the Covenant have accidentally released the Flood, a parasitic alien race capable of spreading itself by overwhelming and infesting other sentient lifeforms. Keyes falls victim to them while looking for a cache of weapons. The release of the Flood prompts 343 Guilty Spark to recruit the Master Chief in retrieving the Index, a device that will activate Halo and prevent the Flood from spreading beyond the facility. After the Master Chief retrieves and begins to use the Index, Cortana re-appears and warns him against the activation. She has discovered that Halo's defense system is a weapon designed to kill all life in the galaxy. When confronted with this information, 343 Guilty Spark states that the installation technically only has a maximum radius of twenty-five thousand light-years, but that its pulse would trigger other similar installations as well, killing all sentient life in the galaxy.
While fighting the Flood, the Covenant, and Guilty Spark's Sentinels, the Master Chief and Cortana attempt to destroy Halo before 343 Guilty Spark activates it. Cortana discovers that the best way to destroy Halo is to cause the crashed Pillar of Autumn to self-destruct. However, Captain Keyes' authorization is required to destroy the ship. By the time that they reach Keyes, he has been infected and turned into a Brain Flood. The Master Chief retrieves Keyes' neural implants directly from his brain, and Cortana activates the Autumn's self-destruct sequence. However, 343 Guilty Spark reappears and deactivates the countdown, discovering the record of human history in the process. The Master Chief manually causes the Pillar of Autumn's fusion reactors to begin to melt down, and the Master Chief and Cortana narrowly escape the destruction of the ring via a fighter.
O'Donnell has remarked that he "sat with the level designers and 'spotted' the level as though it was a movie, with the knowledge that the music would have to be malleable rather than static.... [T]he level designer would tell me what he hoped a player would feel at certain points or after accomplishing certain tasks". Based on this information, O'Donnell would "go back and develop appropriate music cues, then have the designer script the cues into the level, and then we'd play through it to see if it worked as desired." He explained that the use of music in Halo is sparse because he believes that "[music] is best used in a game to quicken the emotional state of the player and it works best when used least", and that "[if] music is constantly playing it tends to become sonic wallpaper and loses its impact when it is needed to truly enhance some dramatic component of game play."
At E3 2000, the first trailer of Halo was well-received. The version shown there differed greatly from the one exhibited previously, marking the first major overhaul in the game's development. At this point, Halo was a third-person action game, in which a transport starship crashlands on a mysterious ring world that orbits a star. Early versions of Covenant aliens appear in great numbers and loot what they can, and war erupts between them and the humans. Unable to match the technologically advanced alien race, the humans on the ring world resort to guerrilla warfare. This version of the game featured Halo-specific fauna, which were later dropped because of design difficulties and the creatures' "detract[ion] from the surprise, drama and impact of the Flood."
As rumors had predicted, Microsoft announced on June 19, 2000 that it had acquired Bungie Studios. Halo became an exclusive game for Microsoft's Xbox video game console, and Bungie Studios rewrote the game's engine, heavily altering its presentation and turning it into a first-person shooter. Originally a key element, the game's online multiplayer component was dropped because Xbox Live would be unfinished at the time of Halos release. While a playable demonstration of the game at Gamestock 2001 was well-received, critics had mixed reactions to its exhibition at E3 2001. The game was released in North America simultaneously with the Xbox, on November 15, 2001.
On July 12, 2002, a Halo port for Windows was announced to be under development by Gearbox Software. Its showing at E3 2003 was positively received by some critics, with skepticism by others. It was released on September 30, 2003, and included support for online multiplayer play and featured sharper graphics, but had compatibility issues that caused poor performance. Halo was later released for Mac OS X on December 11, 2003. On December 4, 2007, the game became available for the Xbox 360 via download from the Xbox Live Marketplace for 1200 Microsoft Points.
On its release Halo broke sales records; by April 8, 2002, one million units had been sold: this pace was faster than that of any previous sixth-generation console game. During the two months following Halo's release, the game sold alongside more than fifty percent of Xbox consoles. Halo's retail price remained at US$49.99 until November 30, 2003. By July 14, 2003, the game had sold three million copies worldwide, and by January 28, 2004, it had reached four million copies. As of November 9, 2005, Halo has sold over five million copies worldwide.
Halo was critically acclaimed and received an overall score of 97% on Metacritic. Electronic Gaming Monthly observed, "This game has me totally mesmerized ... [It] engages your intellect on a whole different level", and of its multiplayer, "GoldenEye was the multiplayer standard for console first-person shooters... It has been surpassed," awarding the game a perfect score. GameSpot claimed that "Halo's single-player game is worth picking up an Xbox for alone", commenting, "Not only is this easily the best of the Xbox launch games, but it's easily one of the best shooters ever, on any platform." IGN remarked similarly, calling Halo a "can't miss, no-brainer, sure thing, five star, triple A game." Edge called it "the most important launch game for any console, ever", and awarded it a 10 out of 10 score, only the fourth such rating in the magazine's 12-year history. The game received numerous Game of the Year awards, including those of the Academy of Interactive Arts & Sciences, Electronic Gaming Monthly, Edge, and IGN. The British Academy of Film and Television Arts awarded Halo "Best Console Game", and Rolling Stone presented it with their "Best Original Soundtrack" award. According to Xbox.com, the game received a total of 48 awards. Among the specific aspects that reviewers praised were the balance of weapons, the role of drivable vehicles, and the artificial intelligence of enemies.
Although Halos overall reception was largely positive, the game received some criticism for its level design. IGN wrote that "the middle third of the game basically has ... the same level over again." GameSpy gave Halo a considerably lower (abeit still positive) rating than other reviewers, later placing the game tenth on its "Top 25 Most Overrated Games of All Time" list. The site stated that the levels often "degenerated into recycling the same areas over and over until you were bored to tears" and were one of the few reviewers to complain about the lack of online multiplayer play, though Xbox Live had not yet been launched and GameSpy offered its Tunnel service to enable SystemLink games over the Internet Noting the level design as a problem, an article on Game Studies.org stated that the game still "triumphs in understanding the anatomy of the FPS," and is "not so much about 'combat evolved' as the subtitle suggests, but about 'genre evolved'."
Halo's PC port garnered mixed reactions and received a score of 83% on Metacritic. GameSpot stated that it was "still an incredible action game ... [and] a true classic", awarding it 9.0 out of 10. It received a score of 8.2 out of 10 from IGN, who stated, "If you've played the game on the Xbox, there's not much for you here." Eurogamer called the game "a missed opportunity", but stated that the online multiplayer component was "a massive draw ... for Halo veterans".
Halo has been featured at both Major League Gaming and the World Cyber Games. In machinima, the game was used as the basis for the popular Red vs. Blue. The game's sequel, Halo 2, made US$125 million with unit sales of 2.38 million on the first day of its release, earning it the distinction of the fastest-selling United States media product in history. Three years later, Halo 3 shattered that record with the biggest opening day in entertainment history, taking in US$170 million in its first 24 hours.
Another adaptation is the Halo Graphic Novel, a collection of four short stories released in July 2006. It was written and illustrated by well-known graphic novelists Lee Hammock, Jay Faerber, Tsutomu Nihei, Brett Lewis, Simon Bisley, Ed Lee and Jean Giraud. Bungie Studios regards Halo's adaptations as canon.