Cortana

Occupation:Artificial Intelligence/Companion
Debut:Episode 1
Affiliation:UNSC Navy, ONI (Office of Naval Intelligence)
Faction:United Nations Space Command (UNSC)
Race/Role:Human
Gender/Age:Female (programmed personality), 8 years (at time of rampancy)

Advanced AI construct created from a clone of Dr. Catherine Halsey's brain, Master Chief's closest companion.

Personality

IntelligentWittyLoyalProtectiveSarcasticCaring

Abilities

Computer system infiltrat...Data alysis

Notable Items

Data crystal chipHolographic projectors
Wisdom:
"I am your shield. I am your sword."+3 more
Battle Cry:
""Let's go!""

"Don't make a girl a promise... if you know you can't keep it."

character
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Gravemind

Gravemind
Occupation:Flood Compound Intelligence
Debut:Episode 1
Affiliation:Flood Collective
Faction:The Flood
Race/Role:Human
Gender/Age:N/A

Collective consciousness of the parasitic Flood, representing the ultimate threat to all sentient life.

Personality

AncientManipulativeIntelligentMalevolentPatientCunning

Abilities

Collective consciousnessBiological assimilation
Wisdom:
"This one is machine and nerve, and has its mind concluded."+3 more
Battle Cry:
""Let's go!""

"I am a monument to all your sins."

character
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Master Chief Petty Officer John-117

Master Chief Petty Officer John-117
Occupation:Spartan Super-Soldier/Protagonist
Debut:Episode 1
Affiliation:UNSC Navy, Spartan-II Program
Faction:United Nations Space Command (UNSC)
Race/Role:Human
Gender/Age:Male, 49 (chronologically), 41 (biologically due to cryo-sleep)

Legendary Spartan super-soldier and humanity's greatest warrior in the fight against alien threats.

Personality

StoicDeterminedLoyalProtectiveHonorableResilient

Abilities

Superhuman strengthEnhanced reflexes

Notable Items

MJOLNIR Powered Assault ArmorMA40 Assault Rifle
Wisdom:
"Spartans never die. They're just missing in action."+3 more
Battle Cry:
"Let's finish this fight!"+3 more

"I need a weapon."

character
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Master Chief Petty Officer John-117

Master Chief Petty Officer John-117
Race/Role:Spartan Super-Soldier/Protagonist

Legendary Spartan super-soldier and humanity's greatest warrior in the fight against alien threats....

Abilities

Spartan Super-Soldier/Protagonist
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Prophet of Truth

Prophet of Truth
Occupation:Covenant Supreme Leader
Debut:Episode 1
Affiliation:High Prophets, Covenant Hierarchy
Faction:Covenant Empire
Race/Role:Human
Gender/Age:Male

Manipulative leader of the Covent who seeks to activate the Halo rings for religious purposes.

Personality

ManipulativeFaticalRuthlessIntelligentAuthoritarianDeceptive

Abilities

Political manipulationReligious authority
Wisdom:
"Your destruction is the will of the gods, and we are their instrument."+3 more
Battle Cry:
""Let's go!""

"I am Truth! The voice of the Covent!"

character
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Sangheili (Elite)

Sangheili (Elite)
Occupation:Covenant Warriors
Debut:Episode 1
Affiliation:Unknown
Faction:Covenant Empire / Swords of Sanghelios
Race/Role:Human
Gender/Age:Various

Proud warrior race that served as the military backbone of the Covent before the Great Schism.

Personality

HonorableProudWarrior-likeNobleSkilledTraditiol

Abilities

Master combat skillsEnergy sword mastery
Wisdom:
""Every journey begins with a single step.""
Battle Cry:
""Let's go!""

"Wort wort wort!"

character
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Thel 'Vadam (The Arbiter)

Thel 'Vadam (The Arbiter)
Occupation:Elite Warrior/Former Covenant Commander
Debut:Episode 1
Affiliation:Elite Separatists, UNSC Alliance
Faction:Swords of Sanghelios (formerly Covenant)
Race/Role:Human
Gender/Age:Male, Unknown (mature Elite)

Former Covent Supreme Commander who becomes an ally to humanity after learning the truth about the Halo rings.

Personality

HonorableProudWiseDeterminedNobleReformed

Abilities

Master swordsmanMilitary tactics

Notable Items

Energy SwordArbiter Armor
Wisdom:
"What would you have your Arbiter do?"+3 more
Battle Cry:
"For Sanghelios!"+3 more

"Were it so easy."

character
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Thel 'Vadam (The Arbiter)

Thel 'Vadam (The Arbiter)
Race/Role:Elite Warrior/Former Covenant Commander

Former Covent Supreme Commander who becomes an ally to humanity after learning the truth about the...

Abilities

Elite Warrior/Former Covent Commander
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Unggoy (Grunt)

Unggoy (Grunt)
Occupation:Covenant Infantry
Debut:Episode 1
Affiliation:Unknown
Faction:Covenant Empire
Race/Role:Human
Gender/Age:Various

Small, methane-breathing aliens serving as cannon fodder in the Covent military hierarchy.

Personality

CowardlyLoyalNumerousExpendableChattyFearful

Abilities

Basic combatEquipment operation
Wisdom:
""Every journey begins with a single step.""
Battle Cry:
""Let's go!""

"Run away! Run away!"

character
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UNSC Marine

UNSC Marine
Occupation:Human Infantry
Debut:Episode 1
Affiliation:Unknown
Faction:UNSC Marine Corps
Race/Role:Human
Gender/Age:Various

Brave human soldiers fighting on the front lines against overwhelming alien forces.

Personality

BraveLoyalDeterminedHumorousResilientBrotherhood

Abilities

Military trainingWeapon proficiency
Wisdom:
""Every journey begins with a single step.""
Battle Cry:
""Let's go!""

"Oorah! Let's get some!"

character
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Ur-Didact

Ur-Didact
Occupation:Forerunner Warrior-Servant
Debut:Episode 1
Affiliation:Warrior-Servant caste
Faction:Forerunner Ecumene (rogue)
Race/Role:Human
Gender/Age:Male

Ancient Forerunner military commander driven mad by imprisonment and torture, seeking revenge on humanity.

Personality

AncientBitterIntelligentVengefulProudTragic

Abilities

Forerunner technology mas...Constraint field manipula...
Wisdom:
"In this hour of victory, we taste only defeat."+3 more
Battle Cry:
""Let's go!""

"So fades the great harvest of my betrayal."

character
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