Halo: Combat Evolved

Overview

Halo: Combat Evolved is a sci-fi first-person shooter developed by Bungie and published by Microsoft for the Xbox (as a launch title) on November 15, 2001.

A spiritual successor to the studio's earlier Marathon series, Halo takes place in the far-future 2525 where humanity's military force (the United Nations Space Command, or "UNSC") is in the middle of an intergalactic war with an advanced collective of alien races (known as the Covenant). Players control Master Chief Petty Officer John-117 (more commonly known as the "Master Chief"), an advanced cybernetic super-soldier (and part of the UNSC's secret SPARTAN program) who is sent out to investigate a mysterious ringworld while being pursued by the Covenant. He is aided by the crew of the starship Pillar of Autumn (namely its commanding officer Cpt. Jacob Keyes and AI construct Cortana).

Along with a single-player campaign (which can be played co-operatively with another player via split-screen), the game features an arena-based multiplayer component for up to four-players split-screen and for up to 16 players through its unique "System Link" setup (where four Xbox consoles are linked together in a local area network, with each console supporting four-player split-screen). Key features of this game includes a limited inventory system (where players can only carry two weapons at a time, and must swap with weapons on the ground) and regenerative shields (which charge over time). The game received numerous sequels and spin-offs throughout the years, mainly for the Xbox line of consoles.

The game also received a port to the PC (in conjunction with Gearbox) on September 30, 2003. This version traded split-screen multiplayer support with online multiplayer for up to 16 players. Along with a Mac release on December 3, 2003, Gearbox released a multiplayer-focused expansion (called Halo Custom Edition) allowing for custom user-created maps, mods, and other content.

The game later received an enhanced port by 343 Industries (in collaboration with Saber) for the Xbox 360. Published by Microsoft on November 15, 2011 as Halo: Combat Evolved Anniversary, this port features updated high-definition graphics (which can be toggled on-the-fly using either a dedicated button and Kinect voice recognition), remastered sounds, Xbox Live co-operative multiplayer, bonus features (including using Kinect voice recognition to give in-combat directives and finding collectible "Skulls" that modify gameplay when active). Although the multiplayer part of Halo is not included, the port includes a restricted version of the multiplayer portion of Bungie's Halo: Reach, featuring six remakes (created by Certain Affinity) of classic Halo maps. The campaign portion (alongside the original Multiplayer) was later included n the Halo: The Master Chief Collection compilation for the Xbox One.

Gameplay

Halo was a revolutionary first-person shooter in the controls department, inventing the concept of using the two analogue sticks to move and aim, while on the PC the player uses the keyboard and mouse. It differs from most others at the time in the damage system, where it has the standard health bar with eight bars which decrease when hit after the shields have failed (can be replenished with health packs). As opposed to picking up an "armor power up" the player always has shields which slowly take damage when hit like a secondary health bar, if hit enough they fail and health begins to decrease, and if the player keeps their head down long enough they recharge. Halo made this style of health regeneration popular within many games made today, and this reason is one of many of why Halo was so revolutionary. Along with popularizing health regeneration Halo also popularized restricting the player to only carrying two weapons at a time, simultaneously solving the problem of cycling through large numbers of weapons on a console pad and forcing developers to make every weapon "count", as the pistol could no longer be a near-useless weapon of last resort, for example.

Power ups include over-shields, health packs, and active camo (invisibility).

Weapons

Human Weapons

• Pistol - A semi-automatic slow-firing handgun noted for its powerful magnum ammunition and high accuracy for close-to-medium ranges (with a 2x magnification "smart scope" that relays data directly to the user's HUD). Formally known as the "M6D Personal Defense Weapon System".

• Assault Rifle - A fully-automatic fast-firing assault rifle useful for suppression and close-ranged combat. Commonly carried by friendly infantry, it features a built-in digital readout featuring its current ammo count and a magnetic compass. Formally known as the "MA5B Individual Combat Weapon System".

• Shotgun - A pump-action shotgun that is deadly in close-ranged combat. Each shell must be fed to the Shotgun (which can hold 12 shells at a time). Formally known as the "M90 Close Assault Weapon System".

• Sniper Rifle - A semi-automatic sniper rifle that is deadly in long-ranged combat (with an electronic scope that supports both 2x and 10x magnification and optional night vision). Each clip contains 4 rounds. The PC/Mac version reduced the maximum zoom to 8x magnification. Formally known as the "SRS99C-S2 AM Sniper Rifle".

• Rocket Launcher - A powerful rocket launcher with limited ammunition and a scope attachment (supporting 2x magnification). Each clip contains 2 rockets. Formally known as the "M41 SSR MAV/AW".

• Flamethrower (PC/Mac/MCC only) - An incendiary weapon that projects and ignites a stream of fuel for close-ranged suppression. The fire trail can ignite players over it, dealing additional damage over time. Can overheat (similar to the Plasma Pistol and Plasma Rifle). Only available in the Multiplayer portion, and is disabled in "Classic" gametypes. Formally known as the "M7057/Defoliant Projector".

• Fragmentation Grenade - A standard timed fragmentation grenade with a three-second fuse. Can bounce off of surfaces. Formally known as the "M9 High-Explosive Dual-Purpose".

Covenant Weapons

• Plasma Pistol - A semi-automatic energy-blasting firearm that is very effective against shielded enemies. Continuously firing causes the weapon to overheat, in which the weapon must enter a cooldown phase. Can be overcharged (by holding down the Fire button) to fire a larger superheated bolt that tracks its targets and deploys an electromagnetic pulse (temporarily disabling vehicles and breaking most shields automatically), although it automatically causes the weapon to overheat. While it does not require reloading, it cannot be replenished by picking up ammo. Formally known as the "Type-25 Directed Energy Pistol".

• Plasma Rifle - A fully-automatic energy-blasting weapon that is very effective against shielded enemies. Continuously firing causes the weapon to overheat, in which the weapon must enter a cooldown phase. While it does not require reloading, it cannot be replenished by picking up ammo. Formally known as the "Type-25 Directed Energy Rifle".

• Needler - A fully-automatic projectile weapon that rapidly fires sharp purple crystalline shards. These shards lock on to enemies for a short time, impale them (dealing some damage), and then detonate for additional damage. Can be dual-wielded. Formally known as the "Type-33 Guided Munitions Launcher".

• Fuel Rod Gun (PC/Mac/MCC only) - Energy-based mortar launcher that launches large explosive radioactive projectiles known as "fuel rods". While these shots deal less damage than rockets (and is affected by gravity), the weapon itself does not need to be reloaded (although it can overheat). Only available in the Multiplayer portion, and is disabled in "Classic" gametypes. Formally known as the "Type-33 Light Anti-Armor Weapon".

• Plasma Grenade - A timed energy grenade that sticks to surfaces (including enemies and vehicles). Unlike the Frag Grenade, the three-second fuse occurs after the grenade sticks to a surface. Formally known as the "Type-1 Antipersonnel Grenade".

Multiplayer

Along with the main campaign (which can be done in single-player or two-player split-screen), the game includes PvP arena multiplayer. This mode supports four player locally (through split-screen) and up to 16 players via System Link (where players link up to four Xbox consoles in a local area network, each Xbox supporting four players through split-screen). Unlike other arena multiplayer games at the time, no bots are supported.

While the PC and Mac ports of the game removed split-screen multiplayer support, they added support for online multiplayer for up to 16 players through GameSpy. Shortly before the demise of GameSpy's service in May 2014, Bungie released an official patch to keep the server list functionality online.

Maps

The base game included 13 maps of varying sizes, only two of which support vehicles. The PC and Mac ports of the game added six additional maps (all of which support vehicles) created by Gearbox.

All maps were later included in Halo: The Master Chief Collection.

Standard Maps

• Battle Creek (2-8 players, symmetrical bases) - Plasma Pistol + 2 Fragmentation Grenades.

• Blood Gulch (4-16 players, symmetrical bases, supports vehicles) - Plasma Pistol.

• Boarding Action (4-16 players) - Magnum + 4 Fragmentation Grenades.

• Chill Out (2-8 players) - Assault Rifle.

• Chiron TL34 (2-6 players) - Magnum + 2 Fragmentation Grenades.

• Damnation (4-8 players) - Plasma Pistol.

• Derelict (4-8 players, symmetrical) - Plasma Pistol + 2 Fragmentation Grenades.

• Hang 'Em High (4-16 players) - Magnum.

• Longest (2-8 players, symmetrical bases) - Plasma Pistol.

• Prisoner (2-8 players) - Plasma Pistol.

• Rat Race (2-6 players) - Assault Rifle + Magnum + 2 Fragmentation Grenades.

• Sidewinder (4-16 players, symmetrical bases, supports vehicles) - Magnum + 2 Fragmentation Grenades.

• Wizard (2-8 players, symmetrical bases) - Plasma Pistol + 1 Fragmentation Grenade.

PC/Mac-Exclusive Maps

• Danger Canyon (4-16 players, symmetrical bases, supports vehicles) - Magnum + 2 Fragmentation Grenades.

• Death Island (4-16 players, supports vehicles) - Magnum + 2 Fragmentation Grenades.

• Gephyrophobia (2-12 players, symmetrical bases, supports vehicles) - Magnum + 2 Fragmentation Grenades.

• Ice Fields (4-16 players, symmetrical bases, supports vehicles) - Magnum + 2 Fragmentation Grenades.

• Infinity (4-16 players, symmetrical bases, supports vehicles) - Magnum + 2 Fragmentation Grenades.

• Timberland (4-16 players, symmetrical bases, supports vehicles) - Magnum + 2 Fragmentation Grenades.

Multiplayer Gametypes

The game includes five game modes (known as "gametypes") built-in, all of which are customizable with numerous options (including weapon/vehicle restrictions, objectives, score limits, and respawn timers). After customizing, players can save these configuration as named gametype variants. The game also includes numerous variants built-in.

All built-in variants were later included in Halo: The Master Chief Collection.

Slayer

Standard deathmatch in free-for-all or team scenarios.

By default, Slayer variants include an instant respawn timer (with a +10 second penalty for suicides). In addition, players who respawn move faster for a short time, and players who score a kill move slower for a short time (both as a temporary handicap for newer players). Warthogs are the only vehicles that spawn and cannot respawn.

Variants

• Slayer - 15 kills to win.

• Slayer Pro - Loadouts restricted to Assault Rifle + Magnum + 2 Fragmentation Grenades. Movement speed does not change after a kill/respawn. Much longer suicide penalty. 25 kills to win.

• Elimination - Respawns disabled. Last player standing wins the match.

• Phantoms - Players have a single target, and switch targets once they killed them. All players are invisible, but each target has a waypoint over them. Motion trackers disabled. Movement speed does not change after a kill/respawn. 5 second base respawn timer. Shorter suicide penalty. 10 kills to win.

• Endurance - Players can only respawn four additional times. The first player to die is the "odd man out" and cannot respawn until someone else dies (in which that person becomes the new "odd man out"). Respawn timer increases every time the player dies (+10 seconds) and decreases every time the player scores a kill (-10 seconds). 10 kills (or remain last man standing) to win.

• Rockets - Rocket Launchers only. Motion trackers disabled. 25 kills to win.

• Snipers - Sniper Rifles only. Motion trackers disabled. Respawn timer increases every time the player dies (+5 seconds) and decreases every time the player scores a kill (-5 seconds). 25 kills to win.

• Team Slayer - Teams enabled. 10 second base respawn timer. 50 kills to win.

Non-Classic Variants (PC/Mac)

• Slayer - All vehicles, vehicle respawns, and new weapons enabled. Movement speed does not change after a kill/respawn. Shorter suicide penalty. 25 kills to win. 20 minute time limit.

• Team Slayer - Teams enabled. All vehicles, vehicle respawns, and new weapons enabled. Enemy players are hidden on the motion tracker. Movement speed does not change after a kill/respawn. 10 second base respawn timer. Shorter suicide penalty. 10 second betrayal penalty. 50 kills to win. 20 minute time limit.

Oddball

A "kill the man with the ball" objective mode (in free-for-all or team scenarios) where players must find and maintain possession of the titular Oddball to score points. They earn points over time by having one player hold onto the ball. Players who hold an Oddball cannot use weapons or equipment, but they can melee enemies for bonus melee damage.

In addition to allowing multiple Balls, changing traits of ball carriers (and non-ball carriers), and whether or not the Ball spawns in a random location, this mode can be used without the Ball so that players instead gain points by being specially "marked" (which they get by killing another marked player, or by killing anyone if nobody is marked).

By default, Oddball variants include a 5 second base respawn timer (with a +5 second penalty for suicides). In addition, players who are able to score points have a hindered movement speed. All vehicles are disabled.

Variants

• Oddball - 2 minutes held to win.

• Reverse Tag - Balls disabled. First player to kill another becomes "It" and scores points over time (at the cost of a waypoint marked over them). Players who kill the It player becomes the new It player. Motion trackers disabled. 2 minutes as the It player to win.

• Accumulate - Balls disabled. Players who gain a kill begin scoring points over time. Players gain additional points over time for every kill they gain and lose the bonus when they die. Motion trackers disabled. 5 minutes worth of points to win.

• Juggernaut - Balls disabled. First player to kill another becomes the "Juggernaut" and can deal stronger damage (at the cost of a waypoint marked over them). Juggernauts can only score points by killing other players and lose their buff by being killed. Warthogs are the only vehicles that spawn and cannot respawn. 10 kills as the Juggernaut to win.

• Stalker - Balls disabled. First player to kill another becomes the "Stalker" and gain both invisibility and faster movement speed (at the cost of dealing weaker damage). Stalkers can only score points by killing other players and lose their buff by being killed. Non-Stalker players are hidden on the motion tracker. Warthogs are the only vehicles that spawn and cannot respawn. 10 kills as the Stalker to win.

• Team Ball - Teams enabled. 10 second base respawn timer. 2 minutes held to win.

Non-Classic Variants (PC/Mac)

• Oddball - Holding the Ball does not hinder movement speed. All vehicles, vehicle respawns, and bonus weapons enabled. 2 minutes held to win. 20 minute time limit.

• Juggernaut - Balls disabled. First player to kill another becomes the "Juggernaut" and can deal stronger damage (at the cost of a waypoint marked over them). Juggernauts can only score points by killing other players and lose their buff by being killed. Being a Juggernaut does not hinder movement speed. All vehicles, vehicle respawns, and bonus weapons enabled. 15 kills as the Juggernaut to win. 20 minute time limit.

• Team Oddball - Teams enabled. Holding the Ball does not hinder movement speed. All vehicles, vehicle respawns, and bonus weapons enabled. 10 second betrayal penalty. 2 minutes held to win. 20 minute time limit.

King of the Hill

A "king of the hill" objective mode (in free-for-all or team scenarios) where players/teams must maintain possession of a marked area (known as the "Hill") to score points. They earn points over time by keeping their position inside the Hill's specially-marked boundary.

By default, King of the Hill variants include a 5 second base respawn timer (with a +5 second penalty for suicides) In addition, the Hill remains at the same location throughout the match and has a waypoint marked over it at all times. Warthogs are the only vehicles that spawn and cannot respawn.

Variants

• King - 2 minutes held to win.

• King Pro - Loadouts restricted to Assault Rifle + Magnum + 2 Fragmentation Grenades. 10 second base respawn timer (with a much longer suicide penalty). 2 minutes held to win.

• Crazy King - Hill teleports to random locations at certain times throughout the match. Instant respawn timer. 2 minutes held to win.

• Team King - Teams enabled. Hill teleports to random locations at certain times throughout the match. 10 second base respawn timer. 2 minutes held to win.

Non-Classic Variants (PC/Mac)

• King - All vehicles, vehicle respawns, and bonus weapons enabled. 2 minutes held to win. 20 minute time limit.

• Crazy King - Hill teleports to random locations at certain times throughout the match. All vehicles, vehicle respawns, and bonus weapons enabled. 2 minutes held to win. 20 minute time limit.

• Team King - Teams enabled. Hill teleports to random locations at certain times throughout the match. All vehicles, vehicle respawns, and bonus weapons enabled. 10 second base respawn timer. 10 second betrayal penalty. 2 minutes held to win. 20 minute time limit.

Capture the Flag

A two-team "capture the flag" objective mode where teams must take possession of an enemy flag and bring it back to their flag zone to score points. Similar to Oddball, players who hold an enemy flag cannot use weapons, but they can melee enemies for bonus melee damage.

By default, Capture the Flag variants include a 10 second base respawn timer (with a +5 second penalty for suicides). Warthogs are the only vehicles that spawn and cannot respawn.

Variants

• CTF - 3 captures to win.

• Invasion - Flag locations are swapped, and teams need to bring the flag from their base to the enemy's base. Players can only respawn four additional times. Instant respawn timer. 3 captures (or remain the last team standing) to win.

• Iron CTF - Flag cannot be returned manually. Double health. 15 second base respawn timer. Teams only have access to 1 Scorpion (that cannot respawn). 3 captures to win.

• CTF Pro - Teams must have their own flag at their base in order to score with the enemy's flag. Loadouts restricted to Assault Rifle + Magnum + 2 Fragmentation Grenades. Much longer suicide penalty. 3 captures to win.

Non-Classic Variants (PC/Mac)

• CTF - Teams must have their own flag at their base in order to score with the enemy's flag. All vehicles, vehicle respawns, and new weapons enabled. Enemy players are hidden on the motion tracker. 10 second betrayal penalty. 3 captures to win. 20 minute time limit.

• Assault - Flag locations are swapped, and teams need to bring the flag from their base to the enemy's base. Only one team has access to their flag at a time (making one team Offense and the other Defense), which alternates in 2 minute intervals. All vehicles, vehicle respawns (shorter than normal), and new weapons enabled. 10 second betrayal penalty. 5 captures to win. 20 minute time limit.

Race

An objective mode (in free-for-all or team scenarios) where players/teams must move towards a series of flags scattered throughout the battlefield (in order to score "laps").

By default, Race variants include an instant respawn timer (with a +10 second penalty for suicides). Warthogs are the only vehicles that spawn and cannot respawn.

Standard Variants

• Race - 3 laps to win.

• Rally - Instead of laps throughout a set of flags, players instead race to a single flag somewhere on the map. Once a player reaches that flag, they score a point and the flag moves to another location. 15 points to win.

• Team Race - Teams enabled. All players in the same team need to score 3 laps to win.

• Team Rally - Teams enabled. Instead of laps throughout a set of flags, players instead race to a single flag somewhere on the map. Once a player reaches that flag, they score a point and the flag moves to another location. All players in the same team need to score 5 points to win.

Non-Classic Variants (PC/Mac)

• Race - All vehicles, vehicle respawns (shorter than normal), and new weapons enabled. 3 laps to win. 20 minute time limit.

• Team Race - Teams enabled. All vehicles, vehicle respawns (shorter than normal), and new weapons enabled. 10 second betrayal penalty. All players in the same team need to score 3 laps to win. 20 minute time limit.

Story

Backstory / The Pillar of Autumn

The plot of Halo: Combat Evolved begins in the year 2525. Humans, under the United Nations Space Command ( UNSC) have harnessed faster-than-light "Slipspace" travel and have colonized hundreds of planets in solar systems across the galaxy. During the Human expansion, they encounter an alliance of alien species, called the Covenant, who are inexplicably intent on the complete eradication of Humankind from the galaxy. Fortunately, the UNSC had previously created a supersoldier program to deal with terrorists, labelling the genetically-modified subjects " Spartans," and equipping the super soldiers with a suit of power armour made of the most cutting edge technology available, that was soon made even more formidable with the addition of energy shields based on stolen Covenant technology.

In August of 2552, the Covenant find the planet Reach, a major Human military stronghold, the second-most well protected planet after Earth herself, and assault the planet with a massive fleet. Reach falls, and most of the Spartans are lost in the battle. One, however, Master Chief Petty Officer John-117, commonly known as simply " the Master Chief," escapes aboard the UNSC Pillar of Autumn, a Halcyon-class battlecruiser, that flees into Slipspace away from Reach at a supposedly random vector. The Pillar of Autumn falls out of Slipspace several weeks later in an unknown quadrant of space, unable to contact any other UNSC forces. There, they find a massive artificial installation, shaped like a perfectly round ring, orbiting a gas giant. Cortana, the ship's onboard AI, notes to Captain Jacob Keyes that the ring's inner concave features a terraformed landscape similar to most terrestrial planets, and even has atmosphere and gravity levels comparable to that of Earth.

Within moments of exiting Slipspace and finding the ring, the Pillar of Autumn is located by a Covenant starship, which was already in the vicinity of the ringworld when they arrived. The Covenant, however, withhold bombarding the Autumn with plasma weapons so close to the ring, and instead deploy infantry to board the cruiser. Just before the Covenant's arrival on-board, the Master Chief is awakened from cryo-sleep, from which he makes his way to the bridge, where Captain Keyes gives him his pistol. Keyes's plan is to crash-land the Autumn on the habitable ringworld. Before leaving, the Master Chief takes the chip that contains Cortana and inserts the chip into his MJOLNIR suit in order to prevent her from falling into Covenant hands. Together, the Master Chief and Cortana make their way through the quickly-deteriorating Autumn, toward the ship's escape pods, where the remaining marines on-board have prepared for evacuation. The Master Chief enters a escape pod, and it jettisons from the Pillar of Autumn as the cruiser careens into the atmosphere of the ring.

Halo / Truth and Reconciliation / The Silent Cartographer

The Master Chief's escape pod crash-lands onto the ring, killing all the marines within and knocking the Master Chief unconscious. After regaining consciousness, the Master Chief learns that other pods have landed safely within the vicinity and Cortana intercepts Covenant chatter revealing that the Covenant have seized the wreckage of the Autumn and have captured Captain Keyes himself, holding him prisoner aboard the Covenant ship Truth and Reconciliation. Collecting what is left of the UNSC Marines, the Master Chief, Sergeant Avery Johnson, and dropship pilot Carol Rawley (known in-game by her callsign "Foe Hammer") make a push for the Truth and Reconciliation, where they plan to rescue Keyes from capture. Upon meeting up with him again, Captain Keyes reveals that he has learned through eavesdropping on his captor's conversations that the Covenant call the ringworld " Halo," and that they deem it not only as a religious relic, but as a powerful superweapon, one with enough influence to give its manipulator the power to control the galaxy. Cortana remarks she had intercepted several transmissions referring to a "control room," and that she assumed the Covenant were looking for a control room to a cruiser damaged in the battle above the ring. Instead, the Covenant are actually looking for Halo's control center. Cortana believes that the Humans can get there first if she can interface with a local mapping station referred to by the Covenant as the "Silent Cartographer".

Committed to stopping the Covenant before they find the Control Room, and reinvigorated after the successful invasion of the Truth and Reconciliation, the marines on Halo begin a large-scale assault for the Silent Cartographer. In the meantime, Keyes gains information regarding the location of a large Covenant weapons cache. Believing he and a group of marines led by Sergeant Johnson can seize the cache, he leaves to make his way there, without the Master Chief, who is sent to find and operate the Silent Cartographer. The Chief is successful in this mission, and learns the location of the Control Room, as Keyes and Johnson close in on the weapons cache, deep inside a dense jungle several hundred miles away from the Cartographer island.

Assault on the Control Room / 343 Guilty Spark

Foe Hammer brings the Master Chief and Cortana as close as she can to the Control Room, where the Master Chief makes a push through heavy Covenant resistance--the heaviest yet seen on Halo--for the Control Room, which is a vast chamber with a holographic Halo rotating around the perimeter and central platform. Upon reaching the Control Room (and locking the Covenant out of it), the Master Chief removes Cortana's chip and uploads her into the terminal. She exclaims that the wealth of information is nearly intoxicating, even for an AI like herself, and mentions that an ancient alien race called the Forerunners built an array of Halos just like this one, millions of years ago. And as she uncovers this information, she stops abruptly. Horrified by something unknown to the Master Chief, she orders him to find Keyes and to stop him from opening the weapons cache "before it is too late."

Leaving Cortana in the locked Control Room, the Master Chief and Foe Hammer hurry for the jungle. Once in the jungle, beneath the fog and foliage canopy, the Chief finds corpses of Covenant soldiers-- Grunts, Jackals, and even Elites--and an abandoned Pelican dropship playing a looping distress message. Traversing the jungle, the Master Chief finds a facility nestled into the side of a bluff--the cache Keyes came to find. Inside the facility, the Chief finds little trace of Captain Keyes, Johnson, or the marines amongst the scattered and panicked Covenant troops and Covenant corpses, but finds massive amounts of alien blood splattering the walls, far more than would be created by being shot by Human weapons. Later, he comes across a single marine who appears to have lost his mind, shooting at anything that moves and telling "those things" to stay away from him, and that he won't let them get him. Deep within the facility, the Master Chief finds a heavy blast door locked from the outside by a UNSC tech-lock. Activating it, the Master Chief opens the door and finds a marine corpse slumped against the door. Another marine's helmet lies nearby on the ground, next to a large pool of blood. The Master Chief links up with the video feed from the missing marine's helmet, which shows Keyes and Johnson investigating the cache before being ambushed by a new, unidentified non-Covenant alien species. The video feed shows Keyes's group completely overrun by the pulpy creatures before the video ends abruptly, citing the marine's death as the cause for disruption.

Moments after viewing the feed, the Master Chief is ambushed by a massive swarm of the small, pulpy aliens, now accompanied by larger Combat Forms. The Combat Forms resemble--and, indeed, are--rotting Covenant and Human corpses, now under the control of the smaller Infection Forms. Fighting his way out to the jungle, killing both former enemies and allies now controlled by the parasite, the Master Chief exits the facility on the far side of the bluff, and is assisted by a number of airborne robots of unknown origin, armed with powerful laser weaponry that seems to be perfectly designed to destroy the mutated creatures. The leader of the robots (which are known as Sentinels) teleports the Master Chief to a raised position atop a gigantic tower, and introduces himself as 343 Guilty Spark, the Monitor of Installation Zero-Four (the Forerunner term for this specific Halo, as there are seven total). Spark exclaims that someone--the Covenant, who he calls an impatient and overzealous group of aliens--has released the Flood, the parasitic lifeform now rampant upon the soil of Halo. Calling the Master Chief a "Reclaimer," the Monitor states the only way to stop the Flood is to activate Halo itself, a task for which they require the Index, a Forerunner tech-key located within a tower called the Library.

The Library / Two Betrayals

The Monitor escorts the Master Chief through myriad waves of Flood Combat Forms, commenting that that the Chief's weapons are highly ineffective against the Flood, and makes several comments regarding the Master Chief's lack of preparedness for Flood containment protocols. On the way, Guilty Spark mentions that the Flood are contained on Halo for study, and that, in the case that the Flood escape Halo, they would consume all sentient life in the galaxy. Once at the Index, the Monitor absorbs the key's data, and teleports both himself and the Master Chief back to the Control Room.

When the pair arrive at Halo's Control Room, Cortana reappears in the terminal just as the Master Chief inserts the Index to activate the ring's weaponry. She impedes the process and uses her command of the ringworld's systems to temporarily disable the Monitor. Cortana derides the Master Chief for falling in step with Spark without knowing the full capability of Halo's power. "Halo doesn't kill the Flood," Cortana explains, "it kills their food. Human, Covenant, whatever. We're all equally edible."

The Chief questions the Monitor, who seems strangely confused that the Master Chief was ignorant to this knowledge--as though he should have known this before. When Cortana absorbs the Index's data and is reinserted into the MJOLNIR armor, the Monitor summons a squad of Sentinels to attack the Master Chief, who now fights a war on three fronts--Covenant, Flood, and Sentinels. Cortana and the Master Chief escape, and Cortana--having completely assimilated the vast breadth of Halo's information--tells the Master Chief that the only way to guarantee Halo cannot be fired, which would trigger the rest of the rings in the array and thus destroy all sentient life in the galaxy, is to destroy it entirely, and that the only way to destroy Halo is to detonate the fusion core inside the wreckage of the Pillar of Autumn, and that the only way to detonate the Autumn's core is with a special set of passcodes contained in a chip implanted in the brain of Captain Keyes. Therefore, he must be rescued at all costs.

The Master Chief destroys the three generators powering the majority of Halo's central functions, buying enough time for Cortana to find Keyes before the Monitor can reboot the ring's arsenal. With that done, she determines that Keyes--alive or dead--is on-board the now Flood-controlled Truth and Reconciliation.

Keyes / The Maw

Cortana manages to transport them to the Truth and Reconciliation via a teleportation tactic similar to that which the Monitor uses. Immediately, Keyes, sounding pained and on the verge of death, radios the Master Chief to turn back, to leave Halo by any means possible. The Flood, having completely overrun the ship, gather piles of Covenant corpses in the two largest rooms for some unknown purpose (later entries in the series imply that this was in preparation for the construction of a Gravemind). And as the Chief makes his way toward Keyes, he learns that the Flood are repairing the Truth and Reconciliation, planning to leave Halo in order to consume more sentient life. The Chief finds Keyes, but finds him too late. Keyes is totally consumed by the Flood and has been absorbed into a large, fleshy growth of Flood tissue. Cortana remarks that Keyes wanted them to leave by any means possible, and the Master Chief obliges, punching his hand into the softened skull of the deceased captain, physically removing the chip from within. Black-armored Covenant special operatives arrive on the ship to thwart the Flood threat, and they are distraction enough for the Master Chief to hijack a Covenant Banshee and escape the Truth and Reconciliation.

As the sun rises on Halo, the Master Chief's Banshee reaches the Autumn, which has already been occupied by Flood and Sentinel forces since the Flood incursion. At the Autumn's bridge, Cortana uses Keyes's chip to activate the self-destruct sequence, but it is stopped by the Monitor, who has taken full control of the ship's remaining functional systems. Although Cortana has finally run out of ideas, the Chief suggests they do it the old fashioned way: damage the fusion core using grenades or rockets, rendering it unstable to the point where detonation becomes inevitable.

The Master Chief fights through waves of Covenant, Flood, and Sentinels, all assaulting each other as well as the lone Spartan, who appears to be one of the only Humans left alive on Halo. After detonating the four reactors, the Chief successfully damages the fusion core and starts the inevitable chain reaction. Foe Hammer, having survived the Flood infection in her Pelican, tells the Master Chief to grab a Warthog from the vehicle depot and meet her at a landing pad just under a kilometer down the length of the ship, where she can extract him and Cortana and escape the destruction of Halo. Driving over Flood forms and dodging Sentinel laser cannons and Covenant plasma fire, the Chief makes it to the landing pad with minutes to spare, but Foe Hammer is ambushed by a pair of Covenant Banshees, and her Pelican crashes and explodes.

With no time to mourn their most recently slain friend, the Master Chief and Cortana make one final charge: a Longsword starfighter is docked at the far end of the ship, and if they can make it there in time, they can use it to escape Halo. Seconds before the Autumn detonates, the Chief boards the Longsword and flees the ring, managing to get to a safe distance just before the nuclear reaction creates a shockwave whose power is enough to shatter Halo entirely, sending massive, concave shards careening through space. The Chief uses the Longsword's sensors to search the debris field, hoping that other UNSC marines escaped the ring before its destruction. But there is nothing left but dust and echoes.

Cortana states that with Halo and the Covenant fleet destroyed, everything is finished, hinting at a sense of optimism. But the Master Chief, removing his helmet, remarks that the two of them are " just getting started."

After the credits, 343 Guilty Spark is seen flying through space amongst the giant scraps of the ring.

Characters

• The Master Chief - Spartan 117, he is Humanity's last, best hope against a ruthless alliance of various alien races known as the Covenant.
• Cortana - An incredibly advanced AI who directs Master Chief through the game as she monitors troop movements and relays waypoints.
• Captain Jacob Keyes - The Captain of the Pillar of Autumn. Leads troops after crash landing on Halo until he is infected by the Flood.
• 343 Guilty Spark - Robotic AI monitor of Halo. Uses the player to carry out his purpose of activating the ring world. May have gone insane after running unchecked for thousands of years.
• Staff Sergeant Avery Johnson - The iconic sergeant that supports the Master Chief and commands the marines.

Development

The first known iteration of Halo was a real-time strategy game (something that was later achieved by Halo Wars) cited by Bungie to be "basically Myth in a sci-fi universe." Steve Jobs presented the first public viewing of Halo at MacWorld 1999 during his keynote address. At the time, Halo was going to be a simultaneous Mac and Windows release. Prior to MacWorld Halo had only been viewed behind closed doors by journalists who were required to sign a non-disclosure agreement. At this point Halo was intended to be a third-person-action game, in which a ship crash lands on a ring world and early versions of the Covenant aliens appear simply to loot what they can with the humans forced to resort to guerrilla warfare.

The first official trailer was shown at E3 2000 and was well received. One month later on June 19th 2000 Microsoft announced that it had acquired Bungie Studios; Halo had become an Xbox exclusive. Bungie rewrote the game's engine and the game became a first person shooter. Playable demos carried mixed reactions up to its release simultaneously with the Xbox on November 15th, 2001.

Post-release

Halo Custom Edition

Halo: Custom Edition is a free expansion that requires a key code from Halo: Combat Evolved to be played. Custom Edition was made by Bungie Studios, which was ported to the PC by Gearbox Software. Halo CE was released by Gearbox as an unsupported version of the original game. However, users do not need to pay to play it, as it is downloadable from selected websites. Halo Custom Edition has the ability to load and play user-created content and maps created with the Halo Editing Kit. Many custom levels have been created by dedicated members of the modding community and have been posted for download at a large number of websites.

Custom Edition's Halo Editing Kit let people create many things including:

• Level geometry
• Bitmaps
• Player Character
• Weapons
• Vehicles
• Sounds
• Game Interfaces
• Level Scripts and Interactivity
• Objects
• Special Effects
• Animations
• Single Player Modifications
• HUDS

Halo: Combat Evolved Anniversary

Developed by 343 Industries (in collaboration with Saber for the campaign and Certain Affinity for the multiplayer) and published by Microsoft for the Xbox 360 on November 15, 2011, Halo CE Anniversary was released on the tenth anniversary of the Halo franchise. It is a fully-remastered version of Bungie's original Halo: Combat Evolved.

While the original gameplay, physics, and controls remain intact, the campaign includes remastered sounds and an updated high-definition graphics engine that can be toggled on-the-fly (using both a dedicated button and Kinect voice recognition). Kinect voice recognition can also be used to give in-combat directives and scan the environment for a unique Halo encyclopedia. The game also includes new extras, such as achievements, Xbox Live co-operative multiplayer, collectible "skulls" (which modify gameplay when activated), and hidden terminals that provide plot information for Halo 4.

The game also includes a restricted version of the multiplayer portion of Bungie's Halo: Reach, featuring six remakes of classic Halo maps (Beaver Creek, Damnation, Hang 'Em High, Prisoner, and Timberlandfrom Halo: Combat Evolved, and Headlong from Halo 2) and one unique Firefight map (with architecture resembling the levels of Halo: Combat Evolved). New copies of the game also included a redeemable marketplace code so that players of Halo: Reach could download the maps for free (where other players must purchase the Anniversary Map Pack for 1200 msp, or $15).

Players who pre-ordered the game received two bonuses: a Dress-Up item for their avatar that resembles the Master Chief, and a special game-modifying Skull (titled the Grunt Funeral Skull) that causes killed Grunts to violently explode with the force of a Plasma Grenade).

Soundtrack

Marty O'Donnell & Michael Salvatori created the soundtrack for Halo. The soundtrack was released on CD shortly after the release of the game.

PC System Requirements

• Windows 98SE/ME/2000/XP -- 128 MB RAM
• Processor - 733 MHz
• Hard drive - 1.2 GB
• Video Card - 32 MB/ 3D T&L capable

Online/Multiplayer Requirements:

• 56.6 kbps modem or LAN; broadband to run a server

Other:

• 8x CD, sound card & speakers/headphones

Mac System requirements

Minimum

• Macintosh computer with 800 MHz or faster processor
• Mac OS X v10.2.8 or higher
• 256 MB RAM
• 32 MB AGP Video Card (GeForce 2MX/ATI 7000 or better)
• 1.4 GB hard disk space

• Internet or LAN connection required for online play

Recommended

• 1GHz G4 or faster processor
• Mac OS X v10.3
• 512MB RAM
• 64MB AGP Video Card (GeForce 4ti-ATI 9000 or better)