Warhammer 40k Wiki
Warhammer 40k Wiki

The Legio Tritonis ("Dark Tide") was the first Blackshield Legio, a Titan Legion that fought only for itself and neither for the Imperium of Man nor for the Traitors of Chaos during the Horus Heresy.

Hailing from the Forge World of Arachnus, during the middle years of the galaxy-wide civil war of the Horus Heresy, the planet and its two neighboring moons became engulfed in internecine conflict.

Seeking to overthrow their perceived oppressors, which happened to include both the Emperor and the Warmaster Horus, this conflict eventually resulted in the rebellious elements having uncontested control of both Arachnus and its moon Iktomia, though battle still raged on the other moon, Nizkara, led by the fierce resistance of a handful of Legio Venator Titans.

Arachnus declared itself an independent state and fought both Loyalist and Traitor alike during the Heresy.

Originally formed from the secessionist faction of the Loyalist Legio Venator, Arachnus' newly founded Titan Legion renamed themselves the Legio Tritonis in homage to the three celestial bodies of their homne system -- Arachnus and its two moons.

Others would come to know them by another name, calling them "Dark Tide" for the widespread destruction they brought down upon any who opposed them before they were finally purged from Arachnus by a Loyalist assault led by their own kin of the Legio Venator.


Legio Tritonis colour scheme as displayed by the Warlord-class Titan Chainbreaker.

Horus Heresy

Though ostensibly a new Legio formed during the Cataclysm of Iron, the Legio Tritonis could trace its legacy back to the Age of Strife, when these god-engines still served under the banner of the Legio Venator.

The ideological splits between the two disparate elements of the Legio Venator were to bring much strife to Arachnus come the Horus Heresy. When news of the Warmaster Horus' treachery reached Arachnus, there was much contention within the upper hierarchies of the Forge World as to which side in the developing conflict Arachnus should take.

In answer, the far-ranging elements of the Legio Venator were recalled to Arachnus and, after standard years of debate, those Iron Spiders that had spent great periods of time away from their founding world appeared to emerge victorious following the outbreak of warfare within the Belt of Iron.

In answer to calls for aid, the veterans of the Great Crusade were sent across the region, bringing war to the Warmaster's allies. In doing so, Arachnus was emptied of many who held ironclad loyalty to the Imperium, a circumstance that proved calculated in its arrangement.

Mere solar months after much of the Legio Venator swore renewed allegiance to the Emperor, Arachnus declared its own independence from the Imperium, purging the Forge World of those who still supported the Emperor and bequeathed the secessionist elements of the Legio Venator with a new name -- the Legio Tritonis, the "Dark Tide."

Legio Tritonis was named in honour of the three celestial bodies that made up Arachnus, these being the planet itself and its two moons. Many of those who joined the rebellion against the Imperium possessed solar decades, or even Terran centuries, of service and remembered an age when Arachnus was ruled only by its people.

After purging their homeworld of any who sided with the Imperium, maniples of Dark Tide Titans embarked upon a ruthless campaign of destruction across the Belt of Iron region of the galaxy, warring with both Loyalist and Traitor alike as they sought to secure a glorious new age solely for the Forge World of Arachnus.

When the Legio Venator finally returned to Arachnus, wrestling it from the grip of those Traitors who had spat upon their oaths to the Imperium, the Forge World of their founding was but a shadow of its former glory, lesser than the forge-fortress of M'Khand (their temporary home) and perhaps never to return to what it once was.

Notable Campaigns

  • Cataclysm of Iron (010-015) - In the region of the galaxy home to many minor Forge Worlds known as the Belt of Iron, the Horus Heresy brought many long-held grudges to the surface. Realising how crucial the Forge Worlds in the area were to both sides in the conflict.
    • Dark Tide (218.011.M31) - In the years following the events in the Isstvan System, the loyalty of the Forge Empire of Arachnus became suspect. Within the borders of Arachnus, two warring ideological sects fought a political battle that would determine the allegiance of the Forge Empire. Those that had spent solar decades serving in the Great Crusade held great respect for the Imperium and its values and advocated for standing against the Warmaster Horus in aid of the Emperor, while others claimed the unfolding civil conflict served as the perfect backdrop against which Arachnus could once more seize control of their own independence. This disagreement appeared settled following repeated expressions of concern from the wider Imperium, interlaced with implicit threats from the Imperial Household itself, that bade the Forge World resume shipments of aid and supplies to worlds both within the Belt of Iron and further afield. In answer, the rulers of Arachnus dispatched several fleets, and several dozen Legio Venator god-engines, to aid the Loyalist push into the Ny'Drinah sub-sector. It fell to those who had served widely during the Great Crusade to lead the war efforts of the Legio Arachnus within the Belt of Iron, while other elements were given the task of guarding the borders of Arachnus. Close observation of deployment records show that the distribution of military strength outside the borders of the Forge Empire of Arachnus largely consisted of those who refused to support the idea of independence, placing them far removed from the Forge World. The first reports of conflict upon Arachnus itself came in the closing days of 010.M31, with data indicating the discharge of weapons fire within the principal Legio stronghold upon the Forge World. Having committed many of the dissenting elements of the Legio Venator to far-flung conflicts, the Titan Legion of Arachnus eliminated those who still resisted rebelling against the Imperium before moving to purge the Forge World of other dissenting opinions. In what would come to be known as "Trident's Purge," conflict engulfed Arachnus and its two inhabited moons, Iktomia and Nizkara, with later estimates placing the death toll at several million and 37 Titans recorded as having fallen. Following three solar days of extended conflict, the rebellious elements of Arachnus had uncontested control of both the Forge World and Iktomia, though battles still raged upon the surface of Nizkara due to fierce resistance led by a handful of Loyalist Legio Venator Titans. In a message to all within the Belt of Iron, Arachnus pronounced itself as an independent state, declaring punishment for any who defied them. In recognition of this new state of affairs, the traitorous faction of the Legio Venator was renamed the Legio Tritonis in homage to the three celestial bodies, Arachnus and its two moons, from which the Titan Legion hailed. Others knew them by another name, calling them the "Dark Tide" for the widespread destruction they brought down upon any who opposed them.
    • Reckoning (145.013.M31-015.M31) - The loss of Urdesh during the Cataclysm of Iron damaged both the cohesion and morale of the Traitor forces, becoming a symbol of the ascendency of Loyalist forces across the Belt of Iron. While several lesser Forge Worlds such as Tridolii threw themselves on the mercy of the Imperium, others, such as Narunbax, had fallen too far and were in turn crushed by the Legio Venator and the Legio Atarus as the two Titan Legions marched on Arachnus, intent upon recapturing the world in the name of the Emperor. Kalibrax, recognising that the attention of the Loyalists was held elsewhere, retreated inwards, abandoning its allies in an attempt to fortify its holdings. In doing so, the worlds they had conquered were deprived of the presence of the Legio Kulisaetai and with their oppressors removed many of their number rose up once more, casting down those Traitors that remained. Having freed themselves of Traitor rule, many amongst them wished not to stand idle after their long standard years of suffering and gathered in small numbers, seizing control of what ships they could. Together, a vast flotilla of mismatched starships was formed, hundreds in number and eclectic in design. This fleet, lacking a purpose beyond vengeance, fell upon Kalibrax. Millions died against the superior guns of the Forge World yet, as is oft the case in war, numbers proved superior and the fleet seized control of Kalibrax's orbit. Lacking any means of conquering the planet, the Loyalist flotilla vowed to blockade the Forge World until greater forces came to scour the world clean, trapping the Traitors on their planet to do little but await their fate. Arachnus too felt the wrath of the Loyalists. Since announcing their secession, the empire of Arachnus had grown, the name Dark Tide proving apt for their conquests were brutal and swift, and turned upon worlds without a means to defend themselves. These worlds were the first to be reconquered as the Loyalist vanguard carved straight to Arachnus, falling upon its two moons before the wayward elements of the Legio Tritonis could be recalled to defend the planet. On Nizkara, the invading Loyalists found the world heavily contested by those still loyal to the Imperium, the beleaguered defenders having weathered a siege since Arachnus first fell into civil war. The Legio Atarus moved to relieve the moon's defenders, breaking open the Traitor lines and forcing the Legio Tritonis from its surface. On Iktomia, a similar fate befell the Traitors defending it, the full wrath of the Legio Venator brought down upon those who had renounced their oaths and stolen their homeworld. Following the successful conquest of Arachnus' two moons, the Loyalists turned their gaze upon the Forge World proper. With the agreement of those who had been forced into exile from the world, the guns of the two moons were unleashed upon the Forge World, tearing great craters in the planet's surface in order to clear the way for an invading force. Those of the Legio Venator that had defended Nizkara in the Emperor's name were given the honour of being first to stride upon the surface of Arachnus and bring His justice to the Traitors. True conquest was not achieved until after the fall of the Warmaster Horus and the great war that followed, dozens of Titans falling upon Arachnus before the Legio Venator once more reclaimed their home.

Legion Combat Doctrine

Iktomia, the first moon of Arachnus, had long ago altered its production capacity in favour of Warlord Titans, which were better suited to fight the mega-arachnids that once plagued Arachnus.

During the Horus Heresy, this era of blood conflict was seen as a way to enact vengeance against the Imperium who had shackled their world to a distant overlord.

In battle, a vanguard of Arachnus tech-cadres would accompany the Legio Tritonis to battle, deploying esoteric devices that could temporarily shroud a portion of the battlefield in impenetrable darkness. Thus, earning their aptly named moniker "Dark Tide" -- both for the use of this mysterious technology and their penchant for massive destruction.

As many of their princeps possessed solar decades or even Terran centuries of service to their former Titan Legion, many princeps within the Legio Tritonis were natural leaders, able to quickly react to their foes and adapt a battleplan to counter any change in fortunes.

Many Dark Tide princeps were highly respected on their homeworld and had an army of retainers, tech-priests and strategists that would gladly follow them into battle.

These princeps viewed damage to their Titans as the greatest insult a foe could give and would strive to ensure the perpetrator was torn apart in return.

Legion Specific Wargear

  • Radiative Warheads - Uncaring of the damage done to the planets they conquered, the Legio Tritonis quickly implemented the use of warheads that contained a radiation-heavy payload that placed great strain upon void shields.

Notable Titans

  • Chainbreaker (Warlord-class Titan) - Chainbreaker was a Warlord Titan that served the rebellious Forge World of Arachnus during the Horus Heresy. Originally, it bore the name Sonus et Omnissiah, having served under the banner of the Legio Venator since M28 during the Age of Strife. Like many Legio Tritonis god-engines, Chainbreaker was titled anew following the foundation of the new Titan Legion, shedding its old identity in a public act of renewal.

Notable Personnel

None listed in current Imperial records.

Legion Appearance

Legion Colours

This rebellious Titan Legion's colours are primarily white with grey painted on their god-engine's massive shoulder plates and portions of the Titan's head.

Grey and white iconography was often used, as well as grey chevrons painted upon Titans' lower legs.

Legion Badge

This Titan Legion's badge is a black triton, a triple-pronged weapon, crowned by an Iron Halo and centred upon a red circlet surrounded by a field of black.