Seven

"Some of you may be wondering - "What's up with this unhealthy obsession with the number 7?" This page offers some insights."

- Brian Jarrard, linking to this very page

"Cause that's the best number. It's like rock. Nothing beats rock or 7."

- Michael Wu

7 Bungie has long enjoyed using the number seven (7) in its games in many prominent ways. Ensemble Studios and authors also have certain obvious seven references in their works about Halo. While almost anything can be made into a reference to something with effort or constructed accidentally through pareidolia, the following attempts to list the intentional references Bungie placed into Halo for the fans to find. As such, not all of these references may be fully accurate, and many of them may be proven to be false at any time. Bungie's obsession with the number seven may be attributed to 7 being considered a lucky number in Western culture. In spite of the fact that the number seven is featured extensively in Bungie's work, it has generated an aura of apophenia. This cultural nuance can be compared to the 23 enigma.

After 343 Industries took over the Halo franchise, references to 7 have continued, possibly as an homage to Bungie.

Cortana Letters and Transmissions

 * Cortana signs her second letter with seven 'X's and 'O's.
 * Cortana sends eight emails. But Letter Three was likely never intended, so seven messages were planned.

Halo: Contact Harvest

 * There were seven space elevators of the Tiara.
 * Seven main maglev train lines led out from each base of the space elevators.
 * Prophet Senior Ministry staffers could manage to travel in their anti-gravity chairs in groups as small as seven.
 * During the evacuation of Harvest, Loki changed the five minute interval for the containers to seven minutes.
 * The first space elevator to collapse was the seventh elevator.
 * Sif's electronics were stored in seven towers in the Tiara's control room.
 * First contact with the Covenant was made on January 17, 2525, i.e. 1/17/2525. 1 x 1 x 7=7. 2+5=7.

Halo: The Cole Protocol

 * Seven ODST's were killed during the attack on the Redoubt.

Halo Wars

 * There are 7 Sangheili deactivating camouflage in the Halo Wars Announcement Trailer.
 * In Halo Wars, both the UNSC Fortress and Covenant Citadel possess 7 expansion sockets.
 * There are 7 types of buildings for each UNSC and Covenant.
 * In the beginning of level Relic Approach, the lockdown on the Alpha Base will not end and the main gate will not open until the player trains five more squads of marines, bringing the total to seven.
 * When playing on Easy or Normal the player begins the level Arcadia City with seven units: six Hornets and Sergeant Forge.
 * The player begins the level Scarab with exactly seven units: 2 Rhinos, 2 Marine squads, 1 Scorpion, 1 Warthog, and Sergeant Forge.
 * There are 7 power nodes that you can destroy to make the Super Scarab's searchlight move slower on the level Scarab.
 * The player begins the level Beachhead with exactly seven units: 4 ODST squads, 1 Hellbringer, Sergeant Forge, and Professor Anders.
 * The cryo pods in the last cutscene are row 3 and 4. 3+4=7
 * Following the events aboard the, Sergeant Forge required seven doses of anti-radiation treatment.

Halo: Evolutions - Essential Tales of the Halo Universe
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Midnight in the Heart of Midlothian

 * Sergeant Michael Baird found fourteen terabytes of information on cancer using Shipnet. 14/2=7
 * Mo Ye's initial plan was to have Baird drive the ship into a red giant fourteen million miles starboard. 14/2=7
 * When Baird first exited the medbay he ran into seven Covenant soldiers (4 Unggoy, 2 Kig-yar, and 1 Elite).

Headhunters

 * Roland-B210 and Jonah-B203 take seven days to reach the Covenant dig site.
 * When Jonah detonates the explosive charges, six Spec Ops Elites and himself are killed, making seven casualties.

The Mona Lisa

 * A Sangheili combat form was brought down "not seven meters from them."

Palace Hotel

 * John-117 fights alongside members of the Eridanus II First Battalion, Seventh Regiment.
 * John-117 was less than seven meters from a Kig-Yar when its head snapped to the side.

The Impossible Life and the Possible Death of Preston J. Cole
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 * Preston Cole was one of seven children (four boys and three girls).
 * Preston Cole's student ID account was 00034. 0+0+0+3+4=7.
 * Ensign Alexis Indara begins management training (Series 7) following the CMA Season of Plenty's bi-annual personnel review.
 * Cole was called before a Board of Inquiry at the Academy at Mare Nubium on June 7, 2492.
 * The UNSC Destroyers which participated in the Callisto Incident in 2494 carried only 7 Ares Missiles.
 * During the Skirmish at Theta Ursae Majoris the had seven Pelicans on standby.
 * "The scattered debris of seven destroyers, however, continued on their previous trajectories."

Halo: Reach
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 * The Announcement Trailer was 1:17 minutes, or 77 seconds long.
 * The Monument to Noble Team is composed of 54,439 individual points of light. (54,439=7*7777)
 * At the main title screen, while various battle sounds are playing, occasionally a clear seven shot burst from an Assault Rifle can be heard.
 * Players begin the game with 7% armory completion.
 * If a player did not purchase the Limited or Legendary editions, the player will only have access to seven Sangheili armor permutations.
 * There is a clearly visible 7 on the Limited Edition black box and on the Legendary Edition.
 * The Halo: Reach limited edition Xbox 360 controller and wireless headset are both marked with the requisition number "//65|59_234|97///" . On the headset, directly before the requisition code, is a larger number 7.
 * There were originally 49 achievements for Halo: Reach. (49=7{{sub|2}})
 * The achievement "KEEP IT CLEAN" requires the player to kill 7 Moa in the second mission of the game's campaign.
 * There are 7 Firefight achievements in the game.
 * The Noble Map Pack includes 7 achievements.
 * Jorge-052's Spartan tag is a reference to the number 7. 0+5+2=7
 * Emile-A239's Spartan tag is another reference to seven, 2+3+9=14, 14/2=7.
 * There are 7 armor abilities: Sprint, Armor Lock, Jetpack, Active Camouflage, Hologram, Drop shield and Evade.
 * The model number of the DMR is M392 (3+9+2=14 and 14/2=7).
 * The Target Locator calls in 7 missiles from orbit.
 * The serial number of a UH-144 Falcon is 1611513214. (1+6+1+1+5+1+3+2+1+4=25, 2+5=7)
 * Anchor 9 is armed with 7 Point Defense Guns.
 * The Collar/Breacher chest attachment has 7 shotgun shells attached to it.
 * There are a total of 7 Scarabs in gameplay, including ones in background battles. Three in the level Tip of the Spear and four in the level Pillar of Autumn.
 * In the mid-level cutscene of the level Winter Contingency, the assault rifle Carter kicks to Noble Six has seven rounds in its magazine.
 * In the beginning of the level Nightfall there is a poster in the first building with 35 black-colored people and 1 red-colored person on it. The red person is on the bottom row 7 places from the left. 35/5='7.
 * On the level Tip of the Spear, the grenade launcher starts off with 7 grenades in Cooperative play.
 * The player begins the level Exodus, with 25 extra Magnum rounds. (2+5=7) In addition, there are 7 rounds left in the starting clip.
 * The first UNSC forces Noble Six after Operation: UPPER CUT meet in the level Exodus are members from Evacuation Team 7.
 * On the level Exodus, the player can find an ad on the "world cuisine" store for a Moa burger combo costing 7.77 cR.
 * In the beginning of the level The Package, the time is shown as 26:16. 26+16=42=6×7.
 * Pressing the hidden switch in the level "The Package" results in the tribute room door opening and 7 Sangheili Generals emerging out of it.
 * There are 14 engines on the back of the UNSC Pillar of Autumn. 14/2=7.
 * At the very end of the credits, in Auntie Dot's grid, the number 7 flashes briefly before fading to the "Lone Wolf" level.
 * At the end of the level Lone Wolf, there are 14 dead Spartans, counting Noble Six. 14/2=7
 * Noble Six battles 7 Sangheili in the ending cutscene of the level Lone Wolf.
 * The ending cutscene of the level "Lone Wolf" take place on July 7th, 2589. July is the 7th month of the year. This is also a reference to Bungie Day. The year is also a seven reference: 2+5=7; 8+9=17, 1x7=7.
 * There are 7 Sangheili Zealots encountered in the game, the first two being in the level Winter Contingency, the next one in the mining facility in Tip of the Spear, a further three in the final section of the level The Pillar of Autumn, and the final one in Lone Wolf who slashes Noble Six with its energy dagger.
 * The Pillar of Autumn utilizes R7 thrust couplings to lift off the surface of Reach.
 * In the multiplayer gametype Invasion, when the countdown goes below 7, it will only recharge back up to 7.
 * It is a common occurrence to get 777 on the matchmaking post game slot machine. The Jackpot for this is 7777.
 * On Legendary difficulty, enemies inflict 77% more damage than on Normal difficulty.

Dr. Halsey's personal journal
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 * Dr. Elias Carver's initial formula for "the matrix mechanics of the socio- and politico-economic vectors of human expansion" utilized 7 dimensional parameters.
 * Six number 7's are written beside a caricature of a dead Carver.
 * Halsey refers to the piezoelectric effect as a 700+-year-old technology.
 * Halsey reports that standardizing UNSC operating systems over the last seven decades left them vulnerable to the insurgency.
 * On July 29, 2549 Halsey states "Only seven weeks to the completion of my personality transfer."
 * Cortana was activated November 7, 2549 or 11/7/49. 49=72 The month and day date may also be a reference to John-117's service number.
 * Miranda Keyes was decorated for her actions aboard the at the Battle of Gamma Pavonis-VII.
 * Halsey mentioned a seventh iteration of the MJOLNIR armor.
 * There are a total of 7 blank pages at the end of Halsey's journal.

Halo 4: Forward Unto Dawn

 * A Corbulo Academy training bunker is designated as "Field Depot 7".
 * Cadmon Lasky tells his brother that his ODST unit engaged in a 7-hour firefight with Insurrectionists.
 * There are 7 fully identified members of Hastati Squad
 * Junjie Chen
 * Thomas Lasky
 * April Orenski
 * Chyler Silva
 * Michael Sullivan
 * Dimah Tchakova
 * Walter Vickers

Halo 4
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 * Cortana mentions that UNSC AIs are supposed to operate for seven years and she has operated for eight.
 * Jul 'Mdama's Covenant faction appears in 7 levels of the game.
 * There's seven Terminals in which the Forerunners are the protagonists.
 * All the Scorpions in the game bear the number 0383. 0+3+8+3=14, 14/2=7
 * There are 14 rounds in an M395 DMR magazine. 14/2=7
 * John-117's cryo chamber is designated "16". 1 + 6 = 7
 * John-117 is awakened by Cortana on July 21st 2557. 21/3 = 7. July is also the seventh month of the Gregorian calendar.
 * The UNSC Infinity is 3.5 miles long. 3.5*2 = 7
 * The MA5D assault rifle can carry up to 224 reserve rounds. 224 ÷ 32 = 7.
 * The Z-130 Suppressor can hold up to 336 total rounds (48 active + 288 reserve). 336 ÷ 48 = 7.
 * Cortana says that John-117 has been in cryo for 4 years, 7 months 10 days. 4+7+10=21, 21/3=7
 * In the level Forerunner, Captain Del Rio can be heard ordering his officers to "increase [Infinity's] speed by point seven."
 * When the Infinity is pulled into Requiem, Cortana calculates its impact site will be 77.8 kilometers away from them.
 * Seven can be seen written on two panels near the front of the Mammoth's Mini-Mac cannon.
 * Pelican Papa Foxtrot 766 is designated "Gypsy Seven".
 * The Ivanoff Station hangar bay John-117 secures is hangar bay 7.
 * Ivanoff Station has 7 excavation-grade HAVOK mines.
 * In Midnight, seven Cortana avatars attack the Didact.
 * In Dawn, there are seven Covenant ships in front of Requiem that are visible.

Spartan Ops
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 * At the end of the opening cinematic of Memento Mori, Spartan Gabriel Thorne is surrounded by seven Sangheili Storm warriors.

Halo: Uprising

 * In Issue #3, a UNSC Marine designated Blue Leader contacts "Site Seven" to establish connection to command.

Halo Legends
{{Scroll box There are 7 different anime shorts in Halo Legends.
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The Duel
There is a 7 in the sky just before the battle in the desert.

Odd One Out

 * 7 residents of planet Cronkee are spoken of in the episode, including the AI "Mama" and the dinosaur.
 * The UNSC ship at the beginning of the episode is numbered "993". The average of these three numbers is 7.

The Package

 * When Frederic-104, Kelly-087 and John-117 enter the Resplendent Fervor, Kelly says, "We got three minutes", indicating that the space battle lasted 7 minutes in their 10 minutes mission time.
 * The battle between John-117 and Thel 'Lodamee lasts 7 seconds.

Homecoming
Ralph-103 mentions to Daisy-023 that it has been 7 years since they were abducted to participate in the SPARTAN-II program. }}

Halo: Cryptum

 * 7 humans belonged to the crew that assisted Bornstellar Makes Eternal Lasting in inevitably finding the Cryptum of the Didact.

Halo: Glasslands

 * Dr. Halsey remarks her old age by reminiscing that she is no longer twenty-one years of age. 21/3=7
 * The completion of the SPARTAN-II augmentation procedures could not be performed until candidates were 14 years of age. 14/2=7
 * New Llanelli was glassed 7 years before the Human-Covenant War ended, as remarked by Tom Muir, who complains that the UNSC's presence during the events of Halo: Glasslands were 7 years too late.
 * Lucy-B091 suffered from a speech impediment for 7 years.
 * Lucy referred to Morse code as a "simple, seven-hundred-year-old system of on-off signals.
 * Mal noted seeing a lot of glassed planets in the last fourteen years. 14/2=7
 * Fred and Mendez go up seven floors in the Forerunner elevator.
 * At the Voi Memorial ceremony, Malcolm Geffen and the other Kilo-Five ODSTs wore their dress uniforms for more than seven hours.

Halo: Combat Evolved Anniversary

 * All the references from the original game apply here.
 * The player has to escape the Flood containment facility within 21 minutes to get the Breaking Quarantine achievement. 21 ÷ 3 = 7.
 * The Anniversary Map Pack released with the game is made up of 7 maps.
 * The Anniversary Map Pack includes 7 achievements.
 * The Halo: Combat Evolved Anniversary manual has 7 pages excluding the front and back covers.

Halo: Primordium

 * As Chakas and Vinnevra visit a crashed Forerunner escape pod, Chakas counts the partial remains of about 7 dead Forerunners.
 * The Forerunner Lifeworker Genemender Folder of Fortune is said to have 7-fingered hands.
 * The victorious Forerunner assault on the humans at Charum Hakkor were staged of 7 slipspace portals.
 * 7000 human warriors and 70 human vessels were assigned to protect the timelock that contained the Timeless One.
 * The flashbacks of 343 Guilty Spark, formerly known as Chakas, primarily take place on Installation 07, one of the 7 Halo rings.

Halo: Silentium

 * Far Nomdagro is located seven lightyears from the Capital system.
 * Audacity had a crew of seven during its expedition to Path Kethona.
 * During a survey of a star system in Path Kethona, Audacity ' s sensor readings are disrupted by unknown objects less than seven hundred million kilometers from the star.
 * The fifth planet in the star system investigated by the Audacity is surrounded by seven rings of icy debris.
 * After discovering a fleet of ancient Forerunner vessels, the crew of the Audacity choose to investigate an outlying group of seven vessels.
 * Among the ancient Forerunner warships are what the Librarian assumes may be classified as sixth- or seventh- order ships.
 * During the Battle of the 78th Thema, twelve Fortress-class vessels are placed as apex control stations for seven hundred thousand Harrier-class vessels.
 * Requiem is orbited by seven ice-covered resource planetoids.

Halo: Escalation

 * In the beginning of Issue #1, Fireteam Jackknife and Sarah Palmer are seen following a lance of seven Covenant members (three Unggoy, three Sangheili, and one Kig-Yar).
 * At the end of the Battle of Ealen IV in Issue #3, a total of seven SPARTAN-IVs die.
 * Issue #7 reveals that seven million people died in the New Phoenix Incident.

Halo: Broken Circle

 * Seven Sangheili are killed during the Skirmish of the Planet of Blue and Red.
 * The Refuge/Broken Circle is divided into seven sections.

Hunt the Truth

 * Benjamin Giraud lives in unit 14 of his apartment complex. 14/2=7
 * Ray Kurzig reveals that Deon Govender died seven years ago.
 * Petra Janecek checked for facts about the Raid on Biko peace talks for seven hours.

Halo Wars 2

 * In the level From the Deep, there are 7 watchtowers stationed around the map.
 * Alice's base in From the Deep has 7 starting structures.
 * On the level Lights Out, Jerome starts with 7 units.
 * There are 7 Marines and 7 Hellbringers at the start of the level Last Stand.
 * There are 7 wave of UNSC reinforcements on the level Last Stand.
 * There are 7 Marines and 7 Hornets in total at The Signal.
 * On the level The Archive, Voridus starts with 7 units.
 * There are total of 7 units from India Company that was not captured on the level Gatecrashers.

Internal

 * List of references to religion in the Halo series
 * List of Marathon References in Halo

External

 * "7" on Wikipedia, the free encyclopedia
 * Bungie.net: The Bungie Code: Septionary: Every 7 Letter Word In The English L...