Cross-Platform Multiplayer Matchmaking: Play on either gaming PC, HTC Vive or Oculus Touch. As a turn-based game, PC verses VR provides no gameplay advantages, only differing user experiences of the world. On the far side of Calth, where night currently reigned, in the sprawling munitions plants of Dainhold, the Word Bearers drove screaming swarms of ragged auxiliaries against the warriors of the XIII th Legion that had barricaded themselves within the fortified manufactorum buildings. Only when the Ultramarines' guns had run dry and the corridors of the manufactoria were strewn with the blasted corpses of the fallen, did Nur Asoktan lead the Cataphractii-armoured elite of the Flayed Hand forwards to hunt down the surviving Ultramarines. Outmatched and cornered, the warriors of Ultramar fought on with combat blades and improvised explosive devices, severing power to several facilities so as to use the darkness to their advantage. The Battle of Calth, also referred to as the Calth Atrocity, was the name given by later Imperial scholars to the treacherous campaign conducted during the early stages of the Horus Heresy in beginning in 007.M31 by the traitorous XVII th Space Marine Legion, the Word Bearers, on behalf of the Warmaster Horus against their hated rivals, the XIII th Space Marine Legion, better known as the Ultramarines. Battle of Phall • Battle of Ravendelve • Ruin of Maerdan • Battle of the Alaxxes Nebula • Pale Stars Campaign • Breaking of the Perfect Fortress • Chondax Campaign • Second Battle of Prospero • First Siege of Hydra Cordatus • Battle of the Furious Abyss • Battle of Calth • Battle of Armatura • Betrayal at Ithraca • Death of Canopus • Shadow Crusade • Crusade of Iron • Doom of Bormina • Defence of Tyros • Defence of the Three Planets • Battle of Ulixis • Ambush at Espandor • Battle of Aquila Atoll • Battle of Drooth II • Percepton Campaign • Battle of Iydris • Thramas Crusade • Fall of Baztel III • Battle of Vannaheim • Second Battle of Paramar • Battle of Constanix II • Mezoan Campaign • Battle of Bodt • Battle of Dwell • Erellian Subjugation • Siege of Baal

Gathering at Saturn those of his Legion who had been embarked on crusades in distant parts of the galaxy, Roboute Guilliman would depart the Sol System mere months before news of Horus' rebellion reached the Emperor's ears. The turbulent state of the Empyrean in those years would see the Ultramarines' main strength journey to Calth by a winding and obtuse trail which would also cloak them from all attempts by Terra to recall them or forewarn them of Horus' actions. The Word Bearers, delayed by the slaughter at Istvaan, would not arrive at Calth until the majority of the XIII th Legion had already gathered, travelling a path of blood and ashes of their creation. Erebus had managed to complete his blasphemous ritual on Calth's surface, which summoned a Ruinstorm to the galaxy's Eastern Fringe -- a monstrous Warp Storm larger and more destructive than anything space-faring humanity had witnessed since the days of the Age of Strife. It would split the void asunder, dividing the galaxy in two and rendering vast tracts of the Imperium impassable for centuries. Enlightenment and knowledge are sundered; the Age of Darkness has begun in earnest. The Emperor’s glorious vision for humanity lies in ruins as his favoured son, Horus, has rejected his father’s light and embraced the corrupting tendrils of Chaos. Civil war has broken out amongst the Space Marines — once brothers, fighting side by side as the galaxy’s protectors, they are now a force divided. Some remain loyal to the Emperor, others have sided with the Warmaster. Nothing is certain, everything is at stake, and the Imperium is split down the middle... Lorgar of Colchis. You may consider the following. One: I entirely withdraw my previous offer of solemn ceasefire. It is cancelled, and will not be made again, to you or to any other of your motherless bastards. Two: you are no longer any brother of mine. I will find you, I will kill you, and I will hurl your toxic corpse into hell's mouth."

Shadow and Iron

Overall: I really enjoyed playing Betrayal at Calth. I love the rich history of the Warhammer 40,000 setting, but more than that I really liked the tactical decision making required during the game. The rules seem deceptively simple at first, but upon playing the game you discover there are a lot of subtle features lurking just beneath the surface. Almost every turn offered significant and meaningful choices, and nothing ever felt automatic. I particularly like the interplay of the various weapon choices and the special effects each weapon has on the enemy. Even the “weakest” weapons can be used to excellent effect by a clever and careful strategist. The six scenarios present unique and interesting challenges for both sides, and Games Workshop has already started publishing additional scenarios in their White Dwarf publication, offering the potential of unlimited replayability. The following information is not to be regarded as officially sanctioned and/ or is not written from an in-universe point of view. A detailed explanation of the term "Trivia" as used in the Lexicanum can be found here.

Ultramarines rally to defend Macragge's Honour from the Daemonic forces unleashed by the Word Bearers Battle of Molech • Breaking of Anvillus • Xana Incursion • Carnage of Morox • Sangraal Campaign • Battle of Arissak • Battle of Perditus • Battle of Sotha • Drussen Atrocity • Scouring of Gilden's Star • Battle of Nyrcon • Battle of Tallarn • Cataclysm of Iron • Battle of Nocturne • War of Drakes • Battle of Pluto • Siege of Inwit • Burning of Ohmn-Mat • Bitter War Twenty minutes before Mark Zero, the Campanile, which had bypassed Calth's outer defence grid, accelerated to full sub-light velocity. At the same time, Sorot Tchure, a Captain of the Word Bearers who had boarded the Ultramarines' cruiser Samothrace, opened fire on Captain Honorius Luciel and his entourage, killing them outright. [2f] Luciel and his seventeen men were regarded by many as the first "official" casualties of the Battle of Calth. [2a]The Ultramarines Force consists of Captain Aethon and one Legion Veteran Tactical Squad. The Word Bearers Force consists of one Legion Veteran Tactical Squad and Sor Gharax. Suddenly the Primarch’s attention was diverted when he looked below their position and saw half a dozen surviving Word Bearers carrying the bloody carcass of Kor Phaeron. Somehow, the wretched First Captain of the XVII th Legion remained alive despite the fact that Guilliman had torn out his primary heart. Drawing their Bolters, the Ultramarines fired upon the retreating Word Bearers, just as their forms shimmered and vanished in a cascade of teleporter energy. The Word Bearers' use of Calth's orbital defence platforms against Calth's sun destabilised it, tore away the outer layers of its photosphere and threatened to cause it to explode as a supernova. The Veridian System's star, its colour changing from a bright yellow to an angry blue as its internal composition shifted, immediately suffered a flare trauma, and shortly after unleashed massive solar flares that irradiated Calth with lethal levels of radiation and stripped away its once dense oxygen-nitrogen atmosphere.