-Captain Jacob Keyes
Armament: Needler
Armor: light

Twenty-six years into his military career, Captain Keyes commands respect as a keen strategist and inspirational leader of his men. He became a minor hero early in his career, when he led a small group of security troops against a Covenant ambush of the colony ship Meriweather Lewis and held them off long enough for the ship to escape. His many decorations and years of combat experience against the Covenant made him a natural choice to command the Pillar of Autumn and its secret cargo.

Notes: Captain Keyes is your friend. :) He is the leader of the Human resistance on Halo, coordinating the various activities of the survivors from the Command Shuttle. You have to rescue and protect him in T&R, where he is armed with, of all things, a Needler, so try not to run in front of him when he decides to start firing. Keep him alive as best you can - you and everyone else on Halo depends on it.

-The Marines
Armament: Assault Rifles, Shotguns, Sniper Rifles, Needlers, Plasma Rifles, Pistols, Frag Grenades
Armor: light-med

A rugged and diverse assortment of soldiers, the Marines on the Pillar of Autumn are fighting a losing battle against the Covenant's superior weaponry and numbers. Under the leadership of Captain Keyes they continue to wage a furious struggle against the Covenant, even as their numbers dwindle. They're the best of the best - but they're only human.

Notes: Marines can be your friends. :) While generally armed with ARs, our dear friend Sarge likes to tool up with Sniper Rifles. In more desperate situations, the Marines will arm themselves with whatever they find, namely Plasma Rifles (Halo, T&R for instance). While generally well-behaved, they can get in the way in battle, and tend to do stupid things such as charging Wraiths with ARs, chucking grenades at the Elite you're meleeing, etc. Other than that, they can be quite helpful, especially when they climb onto your vehicles to provide support (Sarge and Plasma Rifle-armed Marines make for excellent fun). Then again, there is a flipside - Marines gunning in Warthogs will always fire at a target once they spot it - even if it means shooting through an allied tank. And Marines armed with Needlers really suck. Oh well, they're only human. :P

-Cortana

Cortana is the highly advanced AI at the heart of the Pillar of Autumn. Her design allows her to be uploaded into an appropriately configured battle suit for safekeeping. She is capable of hacking into alien computer systems, and has used this skill to intercept Covenant communications during combat. She interprets this data to provide her caretakers with directional waypoints and the best available information about troop movement and strategy.

Notes: Well, Cortana is Cortana, not much to be said there. She is the envy of other AIs, having no behavioral inhibitors. She gives you battlefield advisory, and communicates with the other human survivors for you. She also hacks into the Covenant Battlenet to provide information on enemy strategies. Despite her overall usefulness, some of her motives seem a little questionable…

-the Grunts
Armament: Plasma Pistols, Needlers, Fuel Rod Guns, Plasma Grenades
Armor: light

Approximately 5' tall and relatively weak, Grunts tend to travel in packs and stick close to powerful allies. Individually, they are easy to defeat, but in groups they can overwhelm careless Marines. Their armor seems to house some sort of life-support mechanism. They are known to use a variety of weapons including the plasma pistol, plasma rifle and plasma grenades.

Notes: The Grunt is the basic soldier of the Covenant, their race being the lowest in their society. While looking relatively harmless, they can pose a threat to vehicles, as many Grunts carry Plasma Grenades. On foot, they are more a source of comic relief than resistance, though larger groups can be troublesome. Grunts tend to hang around Elites and Jackals for protection. Beware the Special Ops Fuel Rod-armed Grunts in Two Betrayals, Keyes, and The Maw.
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-the Jackals
Armament: Plasma Pistols
Armor: light + partial non-integrated energy shield

With superior senses of sight, hearing and smell, Jackals serve as scouts and assassins for the Covenant forces. They use plasma pistols and carry a strong energy shield to compensate for their physical weakness: a well-positioned Jackal can hold his own against several Marines, though grenades are effective against them. They stand approximately 5'8" tall.

Notes: A step up from the Grunt in both defence and weapons proficiency. Their shields can deflect most fire, and they use their Plasma Pistol's charged shots to great effectiveness (watch out for Jackals if you just got yourself a brand-spanking new Overshield - they can down it in a single shot). They tend to operate in units of two or more.
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-the Elites
Armament: Plasma Rifles, Needlers, Plasma Swords, Plasma Grenades
Armor: med + full regenerative energy shield

There are a few varieties of the Elite, but all are roughly 8'6" tall and incredibly strong. Their strength allows them to rely on brute force when necessary, but they're quite capable of brilliant battlefield tactics as well. Their natural resilience is augmented with full-body energy shielding which recharges when depleted. They wield plasma pistols, plasma rifles, grenades and needlers.

Notes: Elites are some of the tougher enemies you will face. They are skilled with their weapons, have rechargeable shields, and use cover and such in combat. They are agile and are quite proficient at dodging grenades in some of the higher difficulties. They pilot most of the Covenant's vehicles, so try and take them out if they're near Ghosts, Banshees and Wraiths. There are a couple of different types of Elites, notably the Yellow Elite, with its powerful shield and long jumps, and the Special Ops Elite, which is an excellent grenade thrower.
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-the Hunters
Armament: Fuel Rod Guns
Armor: ü/heavy + alloy shield

Hunters stand 12' tall, though in their combat state they contract to approximately eight feet. Hunters fight with a fuel rod gun integrated directly into their armor. They carry an enormous and nearly-impervious metal shield made of an unknown alloy, which they sometimes use as a melee weapon.

Notes: Hunters are used by the Covenant to protect valuable installations and serve as a last line of defense against you. They are extremely well-armed and armoured, with thick shields that deflect your fire, and Fuel Rod Guns, capable of seriously wounding you and your allies.
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