Tactical Dreadnought Armour, more commonly known as Terminator Armour, was developed for close-quarters melee fighting by Space Marine Terminators, for whom staying power was more important than maneuverability. The technology was originally developed during Mankind's Dark Age of Technology to enable the maintenance crews of spacecraft to operate in hard vacuum or in other adverse atmospheric conditions. It was re-designed during the Great Crusade to replace Power Armour, but was relegated to its current role due to a lack of maneuverability. Very few suits of Terminator Armour were ever manufactured by the Adeptus Mechanicus before the Horus Heresy began and the secrets of the technology's design have now been lost. As a result, every suit of Terminator Armour is treated as an irreplaceable, precious relic by the Space Marine Chapters that own them.
It is an incredibly durable suit comprising an outer shell of heavy-gauge ceramite plasteel composite plates, mounted on an adamantium exoskeleton with servo-assisted interfaces that integrate with an Astartes' own neurological and muscular systems to enhance movement. Its advanced composition allows the wearer to survive hits from firepower that would penetrate tank armour, and it is the heaviest combat armour in any Imperial arsenal, able to withstand tremendous punishment. Offensively, it provides the strength to maintain mobility while serving as a solid heavy-weapons platform in open-field combat. The elite 1st Company of most Space Marine Chapters uses Terminator Armour extensively, and only those Astartes who earn the Crux Terminatus, a special badge of honour said to contain a fragment of the Power Armour worn by the Emperor of Mankind when he defeated Horus at the end of the Battle of Terra, are permitted to wear it. It is said that the Crux Terminatus behaves as a ward that augments the Terminator armour itself, capable of turning aside blows that would threaten even a war engine.
Less frequently, high-ranking members of the Inquisition have been known to wear a form of Terminator Armour sized for an ordinary human occupant. Notably, members of the Ordo Malleus in particular have been known to wear them. However, lacking the genetically-engineered subdermal Space Marine organ known as the Black Carapace, Inquisitors are unable to neurologically interface with the armour, and generally find its bulk much more cumbersome than a Space Marine does.
Almost all Space Marine Chapters maintain some suits of Terminator Armour and usually train some Veteran Astartes in their use, despite their rarity. Terminator Armour is worn in very specific circumstances, such as when the close corridors of a hive city or Space Hulk need to be cleared. Astartes wearing normal Power Armour would not be ideal in such a role; instead they would form a cordon around the Terminators while they carried out the search-and-destroy mission. In the present time, the 41st Millennium, Terminator Armour has become so rare that its use is reserved for those times when it will provide the maximal tactical benefit. Terminators are best used during starship boarding actions where the cramped conditons and tight starship corridors maximise the effects of a Terminator's superior firepower while downplaying his lack of maneuverability, as the environment means flanking attacks are unlikely. Terminator Armour is also deployed into combat on standard battlefields when their heavy weapons can be used for long-range strikes, or they can use teleporter technology to suddenly appear amidst a vast group of enemies where their near-invulnerability to damage can transform them into true force multipliers with little risk of their own loss.
Terminator Armour was first developed during the time of the Great Crusade in the 31st Millennium by the Adeptus Mechanicus of Mars. The Adeptus Mechanicus was receiving a steady influx of new and rediscovered technologies from each planet brought under Imperial Compliance, and, in an effort to stem the horrendous losses of Astartes lives resulting from the ferocious conquests, attempted to design the "ultimate" pattern of Power Armour, which would render a Space Marine virtually unstoppable. The design emerged from a hybrid of standard Astartes Power Armour, the cybernetic shell of a Dreadnought and the armoured hostile environment suits long worn by Terran engineers who worked in difficult environments like debris-plagued orbital space and the radioactive engine cores of interstellar spacecraft. Tactical Dreadnought Armour, as it was called, would turn the Astartes warrior within it into a living tank.
The eventual result of the Mechanicus' travails was only a partial success: the first suits of Terminator Armour did, as intended, afford a level of protection previously unattainable for its wearer. Like Power Armour, the suits were equipped with fibre-bundle synthetic muscles and imposed few movement restrictions upon the wearer, despite their immense weight. But they were also too bulky, and the massive weight made running difficult despite auto-balancers. The suits suffered from voracious power demands and few existing armaments could be carried as the armour's sheer bulk made handling and reloading impossible. But most importantly, the resources in raw materiels and manpower required to craft Terminator Armour were so great that retrofitting the whole of the existing Space Marine Legions with it was simply not feasible for the already thinly stretched logistics of the nascent Imperium of Man.
The Mechanicus refined their concept, and developed weapons adapted for it, like combi-weapons and the Reaper Autocannon. Terminator Armour was then presented in limited numbers to the crusading Legions, who quickly found a use for them. Massively armoured, sealed against any hostile environmental conditions and incorporating their own heavy ranged or close combat armament, Terminator Armour designs soon proved their worth. Terminator Armour, with its ability to maximise the firepower and protection for a Space Marine, became standard on missions in extremely confined spaces like the corridors of a hive city or during a boarding action on a Space Hulk where Dreadnoughts and armoured vehicles could not operate because they were too large to fit.
Several patterns of Terminator Armour evolved in parallel from the Forge Worlds of the Adeptus Mechanicus and the Armouries of the Space Marine Legions. In the 41st Millennium there is no such thing as a "new" suit of Terminator Armour. If an additional suit is required, it is cobbled together from refurbished parts salvaged from the remains of Terminators killed in action. Indeed, as time marches onward, the knowledge of how to fabricate some of the more complex pieces of Terminator Armour has become only a desperate hope in the minds of the Tech-priests of the Mechanicus, whose understanding of science and technology has been slowly decaying for the last 10,000 standard years.
Terminator Armour Variants
Designed during the Great Crusade, and adapted from the heaviest of industrial gear, several types and patterns of Terminator Armour were developed concurrently. Tactical Dreadnought Armour has evolved over the centuries and each of the First Founding Legions had their own deviation from the standard pattern Terminator Armours of the time. The different Terminator Armours that have seen service with the Legiones Astartes and the Adeptus Astartes since the founding of the Imperium of Man include:
- Cataphractii Pattern Tactical Dreadnought Armour - The Cataphractii Pattern of Terminator Armour was originally a prototype for the later patterns of Terminator Armour that was used by the Space Marine Legions and the warriors of the Legio Custodes throughout the Great Crusade and Horus Heresy eras. Whilst similar in many respects to the standard Indomitus Pattern Terminator Armour used by the Adeptus Astartes of the late 41st Millennium, it was set apart by a number of features such as the large, layered pauldrons, the pteruges protecting the elbow and thigh joints, and a helmet that resembled that used by the Mark III Iron Pattern suit of Power Armour. Although the use of the Cataphractii Pattern was rare before the Horus Heresy, some Legions, such as the Sons of Horus and the Iron Hands, possessed a large number of suits, the latter which passed on these suits to their Successor Chapters during the Second Founding.
- Indomitus Pattern Tactical Dreadnought Armour - Originally designed during the Horus Heresy to replace the severe losses on both sides as the civil war dragged on, all of the Traitor Legions' Chaos Terminators now use Indomitus Pattern Terminator Armour and it is also the pattern most commonly employed at present by the Adeptus Astartes because its template is held on many key Forge Worlds such as Mars. In the aftermath of the Horus Heresy, the Ultramarines pioneered the widespread use of Indomitus Pattern Terminator Armour as their Legion was unable to replace the older patterns of Terminator Armour after the loss of many important Forge Worlds during the war. Presently, only the Iron Hands, Minotaurs, and Salamanders Chapters do not have a full 1st Company's worth of Indomitus Pattern Terminator Armour for various reasons. The Iron Hands do not field Terminator Squads; only their officers wear Terminator Armour. The Minotaurs were granted their suits of Terminator Armour by the Inquisition; and the Salamanders encourage their elite Battle-Brothers to manufacture their own arms and armour, leaving their Techmarines free to construct and maintain older and more complex wargear.
- Gorgon Pattern Tactical Dreadnought Armour - A variant of Indomitus Pattern Tactical Dreadnought Armour devised by the Iron Hands Primarch Ferrus Manus and his Iron Fathers, this advanced prototype suit was just going into production at the outset of the Horus Heresy in the early 31st Millennium to supplement the Iron Hands Legion's combat-depleted stocks of Terminator Armour. The design replaced the field generators imbedded in standard Indomitus Pattern Terminator Armour with experimental systems that converted incoming electromagnetic and kinetic energy into bursts of blinding light, able to incapacitate and maim nearby foes. The heat and electrochemical toxin bleed from the armour's systems limited the armour's agility, and its negative side effects required a high level of cybernetic rebuild for its wearer to endure. However, volunteers for this painful modification were plentiful in the Legion's ranks, many deeming it an honour to serve as part of this great endeavour.
- Tartaros Pattern Tactical Dreadnought Armour - Tartaros Pattern Terminator Armour was originally developed concurrently with several other patterns of Tactical Dreadnought Armour towards the closing years of the Great Crusade, and is still sometimes issued at present to the Veterans of a Space Marine Chapter’s elite 1st Company. Perhaps the most advanced form of Terminator Armour ever designed, the Tartaros Pattern shares many systems with the Mark IV Maximus Pattern of Power Armour, and provides greater mobility for its wearer than the Indomitus Pattern, with no loss in durability or protection. Of the shared characteristics between the Tartaros and Maximus Pattern armours, the most obvious is the helmet, though there are other more subtle ones such as the design of the armour on the back of the Tartaros' legs or the vambrace and gauntlets. The Tartaros Pattern also seems to share design characteristics with the Contemptor Dreadnought, most especially in the design of the torso plates. There are also characteristics inherited or derived from the venerable Cataphractii Pattern Terminator Armour, the pauldrons being the more obvious of these.
- Aegis Terminator Armour - The Aegis Terminator Armour used by the Space Marines of the Grey Knights Chapter is similar to the standard Indomitus Pattern Terminator Armour but is inscribed with a complex network of protective prayers, runes and other wards which are psychically charged to provide better protection for a Grey Knight Astartes from the sorcerous powers of daemons and other servants of Chaos. The only major difference between Aegis Terminator Armour and the standard Indomitus Pattern besides the extra layer of psychic protection are the suit's helmet, which has been constructed to be very similar to that used by the ancient Mark III Iron Pattern suit of Power Armour.
There are, according to fragmented Imperial sources, four other patterns of Terminator Armour in existence, but these have yet to be publicly outlined by the Adeptus Mechanicus. Some have been reported to be used by the Dark Angels, Ultramarines and Blood Angels Chapters, but they may or may not have been variants of the standard Indomitus Pattern.
- Chapter Approved 2001: Second Book of the Astronomican, "Crux Terminatus" & "Cult Terminators", pp. 55, 58-59
- Citadel Journal 36, "Talons of Death: New Wargear", pp. 64-71
- Citadel Journal 45, "Space Marine Archive: Terminators", pp. 10-15
- Codex: Chaos (2nd Edition), "Chaos Space Marine Terminators" & "Terminator Weapons", pp. 30, 73
- Codex: Chaos Space Marines (4th Edition), "Chaos Terminators" & "Armour", pp. 28, 86
- Codex: Chaos Space Marines (3rd Edition, 1st Codex), "Chaos Terminators", pg. 10
- Codex: Grey Knights (5th Edition), pg. 63
- Codex: Space Marines (5th Edition), pg. 64
- Codex: Space Marines (4th Edition), pp. 25, 31
- Codex: Space Marines (3rd Edition), pg. 8
- Codex: Space Wolves (5th Edition), pg. 61
- Dark Heresy: Daemon Hunter (RPG), pp. 71, 134
- Deathwatch: Core Rulebook (RPG), pg. 164
- Forge World - Tartaros Pattern Terminator Armour
- Index Astartes IV, "Deep Strike - Tactical Dreadnought Armour"
- The Horus Heresy: Collected Visions (Sourcebook), pg. 189
- The Horus Heresy - Book One: Betrayal (Imperial Armour), pp. 70, 196
- The Horus Heresy - Book Two: Massacre (Imperial Armour), pg. 232
- Warhammer 40,000 Compendium (2nd Edition), pp. 11-18
- Warhammer 40,000: Wargear (2nd Edition), pg. 68
- White Dwarf 305 (UK), "Crux Terminatus"
- White Dwarf 304 (US), "Rise of the Terminators"
- White Dwarf 303 (US), "Index Astartes: Deep Strike", "Crux Terminatus" & "Rise of the Marinies", pp. 18-23, 24-29, 30-35
- White Dwarf 181 (US), "Space Marine Terminators: Tactical Dreadnought Armour", pp. 37-39
- White Dwarf 161 (US), "Deathwing Terminators", pp. 4-7
- White Dwarf 158 (US), "Return to Kalidus: Campaign for The Wolf Guard, Space Wolf Terminators", pp. 30-35
- White Dwarf 142 (US), "Questions and Answers: Aegis Suit", pp. 12-19
- White Dwarf 134 (US), "Space Crusade: Terminators", pp. 4-11
- White Dwarf 122 (US), "Traitor Terminators: Part 2 - Chaos Terminators", pp. 26-35
- White Dwarf 121 (US), "Traitor Terminators: Part 1 - Chaos Terminators", pp. 27-33
- White Dwarf 117 (US), "Close Assault: Terminator Close Combat Weapons", pp. 65-69
- White Dwarf 115 (US), "Command Units: Space Hulk 1st Ed.", pp. 20-31
- White Dwarf 114 (US), "Grey Knight Terminator Squads" & "Cyclone; Terminator Missile Launcher", pp. 11-15
- White Dwarf 113 (US), "Space Hulk: 1st Ed. Preview", pp. 34-39
- White Dwarf 112 (US), "Terminator: Space Marine Tactical Dreadnought Armour", pp. 11-20
- White Dwarf 109 (US), "Terminator Squads", pp. 32-33
- Horus Rising (Novel) by Dan Abnett, p. 161