Greetings, fellow reader! I'd like to thank you for showing interest for my story by accessing it and I hope you will stick with me and enjoy reading it :D I want to make several IMPORTANT observations before going on.

First, this story will borrow names from Halo (because Halo names are the most poetic and best names ever) and from other universes.

Second, remember this is an Alternate Universe (AU), thus I take the liberty to replace and rename certain planets or change a bit the personality of some canon characters (because I may fail to recreate their original personalities).

Third, while some things such as hyperspace and ion cannon technology or magnetic accelerators incorporated into firearms may sound stupid to some of you, I did a little research and came with what one might call an educated guess; the same will apply to fleet sizes of different species.

Fourth, please remember that this is still a science fiction and if you know better than me (i.e. something may not sound feasible for us 2016 + speculation) then please don't bash or start angry rants on that particular subject.

Fifth, the timeline has changed, everything moved by roughly 20 - 30 years; what would be 2157CE and 2186 in the original universe, here is somewhere around 2180 – 2190. FC in 2180 and Reaper War in 2190 or so.

Sixth, the firearms of the Alliance described here ARE NOT the same as the ones you know from the games. The M7 Lancer, for instance, will look different (look XM8 rifle in real life to see how the M7 Lancer would look in my story) and fire different ammo.

Seventh, I changed some dates when several characters were born, kept other characters from the series in the story that might not be supposed to be around and changed a bit how the relay network looks like.

Eight, constructive reviews and feedback is always welcome. Insults and angry rants will be reported and subsequently deleted. Please be civilized.

Ninth, this will feature some disturbing stuff for some readers, from explicit mutilations and war scenes and wounds, to sexual situations (not romantic once, mind you), to explicit language.

Tenth, I'm still a noob!


The start of our story, a story of a species who defied everything and changed the galaxy by making friends and enemies alike. A species that will shake the foundation of what the others knew and will break the cycle. Here begins The Iron Heart of Man


Systems Alliance

Population: 17+ billion humans & 600+ million Smart AI citizens in 20 planets and settlements on other celestial bodies.

Notable planets: planets within Sol system, Eden Prime, Terra Nova, Horizon (all industrial and economic powerhouses), Harvest (bread basket of the Alliance), Reach (military stronghold and primary military shipyards).

Government: federal, democratic, presidential elections take place every 6 years, every planet is represented in the Parliament, Government oversees national projects implemetnation, planetsenjoy autonomy while subordinate to the federation.

Anthem: adaptation of 'Ode to Joy' by Beethoven

Motto: Per Aspera Ad Astra

Primary technology: human made with Prothean influences, developed with knowledge from the archives, especially the shields developed from kinetic barriers, holographic projectors and the QEC. Vital technology such as ion cannons, antimatter reactors, shields, AI platforms and advanced computers are designed with a failsafe mechanism in case it falls on wrong hands; if tampered with, the whole system will self-destruct to preserve secrecy; this was an idea the AIs came up with, so as to not allow human technology to be replicated by possible hostiles. The attitude "us VS them" is still alive in the Alliance.

Policy on foreign powers: assume hostility at first contact and prepare defenses, pursue peaceful relations; "better safe than sorry" attitude is adopted when considering the survival and standing of humanity and its AI compatriots in the galaxy.

Future objective: continuous growth of humanity and their AI friends; steadily increase the military strength of the Alliance to protect itself from any foreign aggression.


Every ship in the Alliance Navy, from destroyer upwards, carries nuclear ordnance. The nuclear warheads, depending on the model, range from mini-nukes, to nukes capable of tearing apart an unshielded battleship in two hits, to nukes capable of planetary devastation.

The Chimera pods are designed to fire the Chimera antimatter missiles. They also allow for the deployment of nuclear ordnance. The Dummy missile pods launch fake missiles. These are simply shells of metal with enough fuel and an onboard computer to direct it to its target. Their role is to put additional stress on the AA defenses and fool it, thus giving the real missiles increased chances of penetrating the defenses and hitting its target.

R&D experimented with nuclear ordnance in the form of shells to be fired through a MAC cannon mounted in turrets. The project was abandoned due terrible design flaws and negative results.

There are other classes of ships in service with the Navy. This article covers only the newest and most numerous classes of warships. Older models are still in service after receiving upgrades in the form of new weaponry and computers. The Mothball Fleet is a planned project that will cover only large vessels such as the battleships, carriers and some cruisers; the rest are to be scrapped after decommission.

Not wanting to open the Mass Relays, humanity decided to keep them inactive and rely on their hyperspace FTL. They were considered possible backdoors into humanity's own home for potential hostile aliens. There are still craft who use real-space FTL based on Prothean technology, they traverse the solar systems and don't venture outside. These vessels are mostly private owned. The nearby Mass Relays were catalogued and mapped, their network drawn based on the direction they were pointing at, thus scientists were able to identify pair Relays. No Relay will be activated until Alliance's first contact.

One of the primary objectives pursued by the humanity was, and still is, to develop technology capable of defeating Prothean technology and other technologies based on Prothean designs. While the Alliance uses Eezo based technology in limited amount, it has the means to defeat kinetic barriers while still employing the barriers for soldiers until a better armor is developed to house new shielding tech (which requires antimatter as fuel).

Systems Alliance Marine Corps

One of the branches of the Systems Alliance Armed Forces. The Marines' role is to provide security aboard the ships, board hostile vessels or stations if need be, and ground deployment. Seldom, they also act as garrisons in the colonies. They tend to be the first in action, as the Insurrection showed, by securing a beachhead for the Army to deploy and continue ground operations. The Marines are trained to operate in every type of environment encountered so far.

Every Marine goes through a short program of genetic enhancements for increased physical performance and an injection of nanites that will do for faster injury recovery and eyesight. Their gear includes: T-Kev Mod S body armor, M7 Lancer assault rifle, M11 pistol, combat knife. The Marine Corps' armor support is usually covered by the Army in terms of securing a terrestrial beachhead. The Corps is also complemented with Paladin mechs.

One of the most infamous units of the Marine Corps is the 501st Special Regiment Hellspawn of the 5th Division. The unit was formed during the Insurrection when multiple Marine units sustained losses in the guerilla war waged with the rebels. These units came together and formed the Special 501st, Hellspawns or Devil's Specials, as they call themselves, nicknames every soldier knows. They were more than ruthless in combat. The unit's reputation was maintained by its commanding officer, Colonel Ray 'Kilgore' Carley, a veteran of the Insurrection. The unit's logo is a burning skull looking upwards with a grin on its face. The 501st Special Regiment will be stationed at Shanxi with an armored unit of the Army once colonization begins. No AIs serve in the 501st.

"Listen, ladies! Only the wretched and unholy will make it into my unit. If you even think about flinching when you see a man's guts spilled on the ground, then you're a bunch of pussies!" (Colonel Ray Carley)

Systems Alliance Army

The Army is the branch of the Armed Forces that is stationed on planets as garrisons. The largest Army garrisons are found on Reach and Earth. They are deployed for terrestrial invasions and peacekeeping in occupied territory. The soldiers of the Army, just like the Marines, received genetic augmentations that increases their fighting ability by granting them better reaction time, increased strength and eyesight. The standard issue body armor is the T-Kev Mod T model. The soldiers use a larger variety of weaponry than the Marines, though the M11 pistol is universal.

The Army is the only branch to command armored units. The armored units include tanks, self-propelled anti-air guns (SPAAGs), artillery in the form of mortars and self-propelled guns (SPGs), anti-air rocket artillery to combat aerial threats in tandem with SPAAGs, infantry fighting vehicles, armored personnel carriers, trucks. Due to economic reasons, the Army still employs the philosophy of MBT (main battle tank) and strives for a single good machine to fill each role.

The Army's MBT is the Apocalypse, the pinnacle of human tank design. Mass production began in 2165 and entered service in 2170, replacing the old and tired Leopard V tank that saw nearly 40 years of active service, a tank based on the 21st century Leopard 2. The Leopard V was salvaged for parts and materiel. Several exemplars are preserved in museums. The Apocalypse boasts one 120mm MAC gun, capable of firing a variety of ammunition types; armor piercing, high explosive, high explosive anti-tank, canister shots and the new ATA rockets (anti-tank & air) to name a few. Its first line of defense is an energy shielding derived from the kinetic barriers fitted on its predecessor. If the shields fail, then there is the advanced Titanium-C battleplate used on warships, slightly modified for tanks. In size, it is comparable to an M1A2 Abrams. The crew consists of a driver, gunner and tank commander. The Apocalypse also has a new AA system; with a new small radar that tracks the aerial threat, it can fire an ATA rocket that will be guided to the aircraft. The Apocalypse MBT is expected to serve up until the turn of the century and some time after it. A variant of the Apocalypse crewed by only a dumb AI is developed.

Smart AIs in the military

Just like their human creators, some of the Smart AIs chose a military career. While other members of the synthetic community are more content to take less riskier jobs, some braver fellas took up arms to defend Earth and her colonies from any threats, foreign or domestic.

The AIs, at "birth", are taught about the world. After "growing up", they are given the freedom to choose their own careers and change them as they want, though it would look really bad on their resume to be job hoppers, as few of them have found out. Many specialize early on in their lives for the career they think is best suited for them.

The AIs that are tasked with managing warships are specialized in interstellar flight, technical expertise, cyber warfare and ship-to-ship combat. They are very dedicated to their work, knowing all too well that human and other AI lives depend on them. Others serve in the Marine Corps and in the Army. Certain AIs who joined the Marines are piloting the Paladin mechs.

Smart AIs have seen action during the Insurrection when they fought rebel fleets and ground forces.

Ais who serve in the Marine Corps or in the Army use a more sophisticated mobile platform that grants them increased performance. When on-duty, AI soldiers equip an armor suit similar to their human comrades, the difference being that their armor is attached on their robotic body and links up with the platform for power to generate the individual shielding. Unlike the T-Kev body armor of the organic humans who rely on modified kinetic barriers, an AI's platform can host a small antimatter reactor to produce the energy to feasibly project a shield. Thus, the AIs take up the role of heavy infantry, their shields capable of taking more damage than the barriers. The barriers employed by the T-Kev armor is based on Eezo technology; they are different in the sense that they are configured to detect and activate for projectiles traveling at speeds much lower than the kinetic barriers employed by Council species are used to.

There is no special treatment showed to either humans or AIs. Just as a man can command a unit, so can an AI that shows the required abilities and proves himself worthy of command. There are pure human units, pure AI units and mixed units. The mixed units are the most common, as organics and synthetics bring their forte points together and increase their fighting capabilities as shown in the Insurrection.


As this codex mentioned many times, the Alliance's infantry weaponry is based on miniaturized magnetic accelerators, the barrels of the firearms redesigned as MAC barrels, and the cartridges redesigned to be compatible while retaining caliber.

The ammunition for the weapons is derived from the 21st century NATO rounds. There is the 5.56x45mm NATO and the 7.62x51mm NATO for assault rifles and light machineguns, the 12.7x99mm NATO for the heavy machineguns such as the M4 Browning (an improved version of the M3, basically the M2 Browning redesigned with the new technology), and the 10mm cartridge for the M11 pistol. Another forte of the new MAC firearms technology is the very low recoil. The lack of an explosive compound and its replacement with an electricity generating compound greatly reduced the recoil of the 21st century weapons, thus accuracy was greatly increased. There are several ammunition types, to name the most widespread: incendiary, armor piercing and hollow-point.

The most widespread guns in use with the Alliance Armed Forces are the M7 Lancer assault rifle, the Minimi Mk II light machinegun (LMG), the M11 pistol and the M4 Browning heavy machinegun (HMG).

The M7 Lancer comes in two variants. The M7L, L short for light, fires the 5.56x45mm NATO round. The M7H, H for heavy, fires the 7.62x51mm NATO round. The M7H has a higher stopping power than the M7L, even if the muzzle velocity is lower than the L variant. The Lancer assault rifle and the XM8 (21st century carbine) have an eerie similarity.

The Minimi Mk II LMG is derived from the 21st century FN Minimi. It fires the same 7.62x51mm as the M7H. The Minimi is a weapon to be reckoned with, capable of tearing apart anything that gets caught in its sights. Every platoon has at least one soldier with a Minimi.

The M4 Browning HMG fires the 12.7x99mm round. It is mostly used as a vehicle-mounted weapon or placed in machinegun nests. It fares well against airborne targets with light armor, as well as LAVs (light armored vehicles), its armor piercing round capable of punching holes through light armor and walls. There are accounts of combatants who had limbs torn off when hit by a 12.7mm fired by the M4 during the Insurrection. Emphasis was put on creating weapons for the infantry that can defeat "the meanest motherfucking aliens out there, put 'em down for good with the least amount of bullets!"

The M11 pistol fires the 10x20mm round. It is the standard issue sidearm for all branches of the military. For a pistol, it packs a really big punch. According to an N2 training in the wilderness of Earth, he was able to stop a Grizzly bear dead in its tracks and put it down with several shots of the M11.

The MP10 is the contemporary evolution of the 20th century MP5. Through progressive improvements on the earlier models, the MP10 was obtained. It fires the same kind of ammunition as the M11 pistol, the 10x20mm round. It is mostly issued to the crews of tanks, IFVs, APCs and other armored vehicles. Some soldiers decide to replace their MP10 with an M7L Lancer. The MP10 is a reliable and powerful submachine gun for low range engagements. It doesn't fare as well as an assault rifle against long range targets.

The arsenal of the Alliance infantry also includes MANPADS (man-portable air-defense system), AT (antitank) systems, grenades, demolition charges, breaching charges, etc.

The standard issue armor of the troopers is the T-Kev. It is based on the lighter Titanium-B alloy and advanced Kevlar. It also comes with kinetic barriers modified to stop projectiles travelling at lower speeds than the projectiles fired by guns employed in the Citadel Council armed forces. The armor suit covers the whole body, leaving a visor for the eyes; there's also the variant with an open helmet for face, but eyes are still protected from dust and small flying objects by a visor. It requires an undersuit to be worn before putting on the armor itself.

The Marines' T-Kev is named T-Kev Mod S, a variant more specialized for action aboard starships, zero gravity or celestial bodies; the S is short for space. It can keep the wearer alive for an hour in the void of space and has small thrusters to help him move around. The Mod S comes with a full helmet. The regular color is dark grey with royal blue stripes on the head, arms and torso or full royal blue.

The T-Kev Mod T variant, T for terrestrial, is mainly used by the Army. It comes in a variety of camouflage patterns, usually a camo pattern adequate to the climate and terrain the unit is stationed in. There is the woodland camo, desert camo and the grey-white-black digital camo for urban areas. Otherwise, the Mod T comes with a light brown paint. T-Kev Mod T is not well suited for combat in outer space like the Mod S is.

The non mainstay armed forces use body armor that isn't as advanced as the T-Kev models. They don't have kinetic barriers, thus relying solely on the armor to stop the projectile. This type of protection is employed by militias and, later on in the Reaper War, by Alliance conscripts.


Fiery Night Contingency is the codename that calls for immediate mobilization of every military asset of the Alliance in a certain system to defend against foreign aggression. The civilian population is evacuated to shelter (bunkers deep underground or into the wilderness) if there is no possibility to evacuate them off planet. Once Fiery Night is declared in a system, a message is sent to Alliance Command and to the Fast Response Fleet (FRF) to immediately dispatch reinforcements and repel the invader.

Noisy Neighbor Contingency calls for immediate mobilization of the Alliance Armed Forces of a sector of space in the case of alien military aggression manifested against its citizens and territory by a neighboring power in the sectors that share the border.

Summer Contingency calls for all available Alliance Navy assets to defend the homeworld (Earth) and Sol system in case it comes under attack from numerous alien forces. Sol system is closed to inbound traffic except ships of the Navy when the contingency comes into effect. The Home Fleet (1st Fleet) is always present in Sol system.

The Hackett-Anderson Protocol is a set of laws promoted by Admiral Steven Hackett in the years following his promotion to Rear Admiral and by Captain David Edward Anderson to safeguard and protect the location of Earth and her colonies in the event of hostile contact with alien forces. The vessels must not set a course straight to a human point of interest after contact with hostile forces; they must jump to a random location before proceeding towards their original destination; that is to confuse anyone with the capability to track them through hyperspace. Should a vessel be incapacitated and close to systems failure or be boarded and the crew overpowered, the crew must purge data from the computers and flood it with garbage data. If the vessel is almost lost to boarders, self-destruct sequence must be initiated. The laws were accepted by the Alliance and further imposed for civilian vessels capable of interstellar travel, be it a ship with a hyperspace FTL drive or Eezo FTL drive. Failure to comply with the Hackett-Anderson Protocol is a major offense and is punishable with death.




Serviceman 1st Class

Petty Officer 3rd Class

Petty Officer 2nd Class

Petty Officer 1st Class

Chief Petty Officer

Senior Chief Petty Officer

Master Chief Petty Officer

Master Chief Petty Officer of the Navy (*)

Chief Warrant Officer


Lieutenant Junior Grade


Lieutenant Commander



Rear Admiral LH

Rear Admiral UH

Vice Admiral


Fleet Admiral

Marine Corps:

Marshal of the Marine Corps


Lieutenant General

Major General

Brigadier General


Lieutenant Colonel




Chief Warrant Officer

Warrant Officer

Sergeant Major of the Marine Corps

Sergeant Major

Sergeant 1st Class

Staff Sergeant



Lance Corporal

Private 1st Class



General of the Army


Lieutenant General

Major General

Brigadier General


Lieutenant Colonel




Chief Warrant Officer

Warrant Officer

Sergeant Major of the Army

Sergeant Major

Sergeant 1st Class

Staff Sergeant



Private 1st Class


SSV Normandy

The SSV Normandy is the first ship of the Normandy-Class. As of 2180 she is still getting her final touches before leaving the Reach shipyards for tests. The ship was designed to operate alone in long deployments with a small crew. The crew mostly oversees and maintains the ship which is run by a Smart AI called EDI and a plethora of Dumb AIs. EDI resides in the ship's systems and uses the latest model of Universal Platform to move around the ship or deploy with Fireteam Immortal. EDI constantly communicates with the Normandy through a miniaturized QEC incorporated into her UP.

The ship's role is to scout deep in enemy territory, even under heavy enemy presence, perform surgical strikes against high value targets on the enemy's home turf, and insertion and extraction of special forces.

She is capable of hyperspace FTL and high speeds in real space. Her stealth systems completely mask her to sensors and visual identification with her upgraded disruptive camouflage system while retaining high speeds. She is 220 meters in length, 95 meters at its widest and 50 meters tall.

Her armament consists of two Chimera missile pods capable of firing the Chimera anti-ship missiles and nuclear ordnance. She also has two super high velocity MAC guns mounted in a spinal fashion but on her 'belly'. Her defensive armament consists of anti-fighter and anti-missile Space Sparrow interceptor missile pods. Her cargo bay (and hangar at the same time) can accommodate two Kodiak shuttles and an Apocalypse MBT or other vehicles. The ground vehicle can be traded for another Kodiak shuttle. Her main armor is one layer of Titanium-C with extra plating in key areas. She also has shield generators.

Captain David Anderson is the commanding officer of the SSV Normandy. Anderson, initially a Marine and N7 graduate, decided to go by Hackett's suggestion and joined the Navy. His previous record and the high scores in the Academy landed him the rank of Commander and then promoted to Captain. He's also known for the Hackett-Anderson Protocol. The pilot is Jeff "Joker" Moreau. Resident doctor is Karin Chakwas.

The Normandy also houses Fireteam Immortal, a newly established N7 special forces small unit for high risk ground missions where failure is unacceptable. Although the team is still young, its members are promising a lot even if they're fresh out of Marine and N7 training. John Shepard is the CO of Fireteam Immortal. Further details will be disclosed in the future.

Shipyards & Fleets

The Alliance commissioned multiple fleets and shipyards to build and maintain these fleets. The shipyards are located in orbit of the primary planets.

The Alliance Heavy Shipyards in orbit over Reach are the largest ones. These behemoths were made to build and repair ships in record time, given the material and human resources are present. Here's where the Prometheus and Titan packers and the Reach-Class Fleet Carriers were built along with a good number of Olympus-Class Carriers and Spirit-Class Battleships. The Heavy Shipyards is where the ODPs are built and shipped where they are needed by the Titans or Prometheus.

The Reach Orbital Shipyards are on the opposite side of the planet in contrast to the Heavy Shipyards. The Reach Orbital Shipyards mostly maintain the ships of the Navy. They're capable of building ships of any class below 2,000 meters in length.

Sol System has three shipyards, Luna Light Shipyards in orbit over the Moon, Earth Shipyards orbiting Earth and the Mars Shipyards in the orbit of the Red Planet. Sol's shipyards are mostly tasked with civilian shipbuilding, freighters or small military ships such as frigates or destroyers, as well as maintaining them.

The Arcturus Shipyards aren't as large as the ones over Reach, but they are big enough to fit a fleet carrier for maintenance or emergency repairs. During peace time, they are mostly used for maintenance and upgrades of ships ranging from frigates to battleships, to merchant ships. The Arcturus Shipyards are linked to Arcturus Station.

The Terra Nova Shipyards were commissioned after the Insurrection when the need for a naval base for the inner colonies arose. This is where the majority of Humanity's merchant fleet makes port. The Terra Nova Shipyards serve as harbor for many vessels and also as shipbuilder of logistics ships for the Navy, merchant ships or private ships.

The First Fleet, also known as the Home Fleet or Sol Fleet, is the largest fleet in the Alliance. The First Fleet is tasked with the defense of Humanity's homeworld of Earth, the defense of Mars and other colonies on other moons across Sol. The fleet can intervene at any time outside of Sol should the need arise. The First Fleet has two Reach-Class fleet carriers (the Antares and Betelgeuse) and is always active and ready.

The Second Fleet is tasked with the defense of Reach and the inner colonies. It is the second largest fleet in the Alliance with the Heavy Shipyards as its homeport. The Second Fleet has one fleet carrier (the Eridani) and, just like the Home Fleet, is always active and ready for action.

The Third Fleet of the Alliance is the third in size and its job is to defend the inner and outer colonies. The Terra Nova Shipyards serve as its homeport. The Third Fleet has only one fleet carrier (the Sirius) in its ranks and, like the other two fleets, is always active.

The Fourth Fleet is based off Arcturus Shipyards and is tasked with the defense of Arcturus Station and the Arcturus Node where many Mass Relays meet and form an important node. While Humanity does not rely on the Relay network, it is vital to blockade the node to prevent unwanted alien incursions. One Reach-Class (the Arcturus) is assigned to the Fourth Fleet. The Fleet is always active.

The Fifth Fleet is inactive during peace time and needs 12 hours up to two days to mobilize before being able to deploy in theaters of war. It is considered a reserve fleet and can "borrow" a Reach-Class from the First Fleet if needed for certain missions. The Fifth Fleet is based off Reach Orbital Shipyards.

There are other much smaller fleets with patrol duties and such. The Fast Reaction Fleet commanded by Admiral Kastanie Drescher is one of the smaller fleets and it is always in stand by for combat. It is the first fleet that joins the fray when a colony or other locations of interest come under attack. There are also the Assault Fleets, a combination of heavy firepower and troop transports for groundside assaults. Out of the 6,000 ships categorized as logistics vessels, most are dedicated for troop transport and deployment; others are simply for shipping food, ammo, spare parts, fuel and the such to the deployed fleets.

It is worth noting that every colony of the Alliance has a small fleet of frigates and corvettes under their jurisdiction, mainly for policing actions within their systems or immediate interstellar vicinity. The corvettes aren't as widely used by the Navy as they are by the colonies' law enforcement, more like an in space Colonial Defense Force. These fleets however can be called upon to join the Navy in times of need and boost its ranks. The corvettes are ships around 75 to 100 meters in length with very light armor and boast a single light caliber turret and one missile pod; there are also models designed with lighter weaponry for AA warfare.

The Alliance also builds and deploys stations called anchorages. These vary in size and are most commonly found in the outer colonies, large mining systems, military outposts, along trade lanes, etc. An anchorage comes equipped with built in defenses in the form of one massive MAC gun mounted in a turret on top of the anchorage and missile pods to fend off any attackers. Depending on the model, they can accommodate ships of up to 900 meters long in its multiple docking bays. They are either prebuilt and shipped to their destination by a Prometheus or Titan packer or are built in modules and assembled at the site where they are needed.

Nuclear Arsenal

The Systems Alliance maintains a good number of nuclear weapons for use in times of war or emergency. Its nuclear weaponry ranges from nukes designed for anti-ship combat, nukes for planetary bombardment, nuclear mines to be used as minefields and nuclear ballistic missiles designed to be used as a planetary defense system along with the Avenger ballistic missiles.

The Dominion nuclear ballistic missiles are designed to be launched against spaceships in orbit or locations on the planet. They are very fast, incorporating some Eezo based technology to make it lighter and a powerful engine allows the Dominion to go very fast, thus capable of hitting its target in high orbit in less than a minute. Its payload is very potent, with antimatter and small tanks with large quantities of compressed gases amplify its thermonuclear yield, making it capable of shredding a Spirit-Class battleship in a single hit if the vessel's shields are down. They are regarded as a last resort weapon due to the possibility of nuclear fallout into the atmosphere.

The Shiva anti-ship nuclear warhead is used to combat enemy vessels. It comes in two variants, the Shiva H and Shiva L, heavy and light. The heavy variant is usually carried by battleships, carriers and cruisers while the light variant is used by destroyers, frigates and some cruisers. They are launched with the use of the Chimera missile pods, a multipurpose missile delivery platform. The Shiva was specifically designed for space warfare but is still capable of dealing massive damage to planetary targets. Its primary payload consists of a healthy dose of antimatter that boosts its standard thermonuclear yield.

The Sunburst nuclear ordnance is used to destroy clusters of small craft like fighters, bombers, corvettes and shuttles. They are in very low numbers compared to the other types of nuclear weapons aboard Alliance Navy warships.

The Apocalypse nuclear warheads were designed for planetary bombardment. They can hit targets on planets and moons. The huge nuclear yield is boosted by the antimatter payload as well, thus giving it the capability of totally wiping a huge city clean off the face of the planet. Considered as a weapon of mass destruction, their use is highly regulated and considered an option if humanity is facing an enemy that is more than willing to commit genocide against the human race. A variant of the Apocalypse is under development, a variant capable of cracking the terrestrial crust of a planet on a radius of 100 kilometers, thus causing massive volcanic eruptions from the magma that resides beneath the layer of rock on any garden world. The Apocalypse nuke has the nasty tendency to leave deep craters if not detonated in the atmosphere, a good weapon against underground installations. The heavy planet devastating variant is developed under the name Project NOVA.

The Havoc tactical nuke is smaller in dimensions with a lower payload, but just as deadly as any other piece of nuclear ordnance. The Havoc is a multipurpose nuke designed for use in space warfare against enemy ships, as well as hitting ground targets on planetary bodies. They are mostly carried into battle by fighters or bombers.

Earth's Cold War era nuclear silos are still maintained to this day as part of the last line of defense against warships in orbit of the planet. They have been refitted to launch the Avenger ballistic missiles and the Dominion nuclear ballistic missiles. Other colonies have this defense mechanism implemented as well (Reach, Harvest, Terra Nova, Eden Prime and Horizon have an extensive defense grid compared to the other colonies).