In The Lore Explainer, we take a deep look at the lore behind our favorite games, movies, and books, and talk about the story behind them and sum up what you need to know and how you can find out more. In this article and the next, we’ll be looking at the lore behind the Shield of Baal campaign in Warhammer 40,000.
When we last examined the scene in the Cryptus System, things were pretty bleak. The Tyranids of Hive Fleet Leviathan had breached the system and laid waste to the defenders on most of its planets, leaving only a few million survivors from worlds which previously housed billions. A single distress signal managed to escape the Shadow in the Warp, calling out into the void for salvation from any foolish enough to walk into the gaping maw of Leviathan.
Shortly after the release of Leviathan, Games Workshop released two additional products for Shield of Baal. The first was Deathstorm, a boxed set featuring models for the Tyranids and Blood Angels – including a new Terminator Captain and the Broodlord – as well as a booklet with the second part of the Shield of Baal saga. Then came Exterminatus, giving us the third and final part of the story and the conclusion to the Shield of Baal arc.

Deathstorm
Deathstorm is more or less exactly the same kind of product as Stormclaw, in that it acted as both an army box with great forces for beginners, a small rules booklet (very good to have), and a campaign booklet detailing the second part of the campaign, acting as a bridge between Leviathan and Exterminatus. Specifically, Deathstorm is focused on the fate of Phodia, where an increasingly desperate and violent battle took place between the Blood Angels Strike Force Deathstorm and Tyranid forces. The key players here are Terminator Captain Karlaen – the then-new Blood Angels Terminator Captain model – and the Spawn of Cryptus, a name given to the then-new Broodlord model.
There’s not nearly as much here as there was in Stormclaw, in part because Tyranids don’t really have characters in the same fashion as Orks. Karlaen stalks the Spawn of Cryptus through the tunnels of the planet and they fight, only for a Carnifex to intervene during their fated duel and the Broodlord to escape. It’s fairly anticlimactic.
There are three missions here:
- Hunters in the Dark –Â While Karlaen and his squad are searching the ruins of the Flaxian Palace for the planetary governor, they’re ambushed by a swarm of genestealers. They fight their way through them, traveling along a long, shadowy corridor. This one actually has the Terminators travel an entire 72″ table, getting attacked repeatedly by respawning Genestealers.
- Storm of Blood –Â Karlaen gets trapped under a fallen statue during a duel. His squad stand by to help him while Death Company and a Dreadnought rush to their aid.
- Shadow of the Beast –Â The only one of the missions where you actually get to use the Broodlord, this third and final mission sees Karlaen and his strike force attempting to rescue Governor Flax and hold off until they can be extracted via Stormravens. This is a last stand type mission where you have to just stay alive until the end of the game.
Otherwise, that’s the long and short of it. The book introduces us to Captain Karlaen, who commands the Blood Angels’ first company. There’s a full novella for Deathstorm, which we’ll be reviewing in a future article.

Exterminatus
As with Leviathan, Exterminatus is another two-book set, with one book for the Rules and the other for the story. Our story begins with Commander Dante, who apparently suspected the Cryptan Shield would fall when he first heard of the encroaching Tyranid Fleet. And while most sensible generals would see the writhing, chittering masses devouring the planet and go “nope,” Dante instead mobilized his chapter for war. The Tyranid fleets’ greatest numbers were concentrated on Asphodex and Lysios, and that’s where the Blood Angels despatched the majority of their forces. The first company were primarily held in reserve, save for Karlaen’s group, who teleported down to Asphodex to act as the tip of the spear and take out the Broodlord there (good job on that one, buddy). Meanwhile the second company were sent to Asphodex under Dante’s command, with a smaller group sent to Aeros. And Lysios would be left to the Flesh Tearers to liberate.
Now you may be asking “How did the Blood Angels get through the Aegis Diamondo?” and you know what? that’s a good question. The answer here is “they knew about some secret thermal tunnels through the Aegis and also spent most of the trip in cryo-stasis.” As a result, they just lost a bunch of chapter serfs during the voyage, which left them more than capable of waging war once they emerged on the other side.

Once they’d plunged through the Aegis, Dante and Mephiston led the bulk of the Blood Angels’ second company into the fray on Asphodex, descending upon the Tyranid swarm and helping the besieged defenders on Phodia. Their first order of business: Liberating the space port and answering the distress calls of the planet’s Astra Militarum defenders.
When Gabriel Seth got the call to help the Blood Angels, he jumped at it. As the head of a legion of extra brutal, crazy vampire madmen, Seth was pretty sick of his allies treating him with suspicion and mistrust. But the Blood Angels were pretty much the only chapter who wouldn’t raise an eyebrow to the Red Thirst/Black Rage, and so Seth saw this as an opportunity for glory that he wasn’t going to get otherwise. When the Flesh Tearers descended on Lysios, they punched through the Tyranid lines and met up with the Adepta Sororitas and nomad forces.
The Necrons Awaken
The fighting across the sector eventually reached the world of Perdita, a Necron tomb World on the outskirts of the system. That big network of solar refractors used to harvest energy from the system’s twin sons? Built off tech originally constructed by the Necrons before humanity even existed after they used their technology to literally pull the stars together to create the violent solar flares so they could farm them. The arrival of Leviathan triggered an early awakening for the forces of the Mephrit Dynasty sleeping beneath the planet’s surface.
Their awakening in turn attracted Anrakyr, who had faced the Tyranids before and found them to be pretty distasteful. The Necron Overlord made a decision to intervene, diverting his fleet to Perdita. He’d meet with Zarathusa, the Overlord of the Mephrit Dynasty and, after the appropriately long-winded greetings required of lords of their status, the two exchanged promises and began to make plans for war.

The Alliance of Convenience
Once the alliance had been made, Anrakyr made for Asphodex. Leading a small force down to the planet, the Traveller marched up to the walls of Port Helos and, in his best High Gothic, requested an audience with the lord of the humans. Which meant Dante. The Chapter Master and Commander Dhrost of the Cadians met with Anrakyr, who made it clear that the Necrons hated the Tyranids and would aid the humans in eradicating them. Of course, Dante did not trust the Necrons in the slightest, but he knew an unwinnable war when he saw one and he was willing to take any help he could get.
The key to victory in this war was the Necrons’ secret superweapon: The Magnovitrium – the massive solar array designed to siphon power from Crypthus’ twin stars – was a relic of the Necrontyr empire, and could be used to ignite the core of the gas giant Aeros, creating an explosion which could scour the stars of the Tyranid ships while Imperial and Necron ships hid behind the system’s other worlds.
The full plan was a four-pronged attack: Anrakyr’s crypteks would retake the Magnovitrium in orbit around Tartoros, while Anrakyr and Dante would fight through the Tyranid forces on Asphodex to secure the cogitator spires needed to regulate the mirror’s output. The Flesh Tearers would secure the array on Lysios, and on Aeros Zarathusa’s legions would secure the vapour-conveyer, which was also apparently important for some reason. Dante relayed these orders to his commanders but also prepared himself to order an Exterminatus if needed.
This doesn’t go wholly as planned – the Necrons fail to capture the Magnovitrium, but the Blood Angels have fortunately sent a back-up force there out of an inherent mistrust of the xenos. The Death Company manage to take back the ancient array with the help from a C’Tan shard of the Burning One sent by Anrakyr to scour the array. They manage to activate the Magnovitrium, which fires a solar beam at Aeros and ignites the whole planet, causing it to erupt and destroy countless Tyranid bio-ships. Most of the Imperial forces were able to shield themselves from the blast – though many still died – while the Necrons just phased out back to Perdita. The Magnovitrium was destroyed, and the Burning One shard was free to fly away and feast on stars again.
In the aftermath, the remaining planets were scoured of Tyranid forces and the remains of the hive tendril fled, intent on rejoining the larger Hive Mind. The Blood Angels had suffered terrible losses, but there was yet a chance Baal could be saved from future invasions.

The Missions
There are eight missions in Exterminatus, and all eight of them focus on the major battles of the campaign, i.e. they fall into the category “Echoes of War.” Unlike those in Leviathan, these are not intended to be played using the Cities of Death rules, and are much more open in their execution.
1. The Avenging Host Descends
The initial descent of the Blood Angels onto Asphodex, whose surface is all but overrun. Dante’s forces deep strike onto the planet in the middle of the Tyranid forces – the entire army must start off the table and arrive at the start of the first turn via Deep Strike.
2. Against the Hive Mind
After the initial attack sends the Tyranids reeling, the hive mind forces regroup and muster a counter-offensive. In this second mission players are meant to field Mephiston and his forces to stave off the counterattack.
3. Breaching the Living Wall
On Lysios, the Flesh Tearers and Adepta Sororitas make a desperate attempt to break through the Tyranid lines to escape their jaws and also the massive approaching tidal wave.
4. Cathedral of Blood
On Aeros, Corbulo’s forces have fought through Tyranid forces to the planet’s primary refining platform, where he now works to defend it against Tyranid forces in order to secure a large amount of the Satryx elixir.
5. Divine Intervention
Following the uneasy alliance brokered with the Necrons, Blood Angel and Necron units join forces to take on countless swarming Tyranid hordes. In this mission the Necrons get a shard of Nyadra’zatha, the Burning One, who can just make walls of fire to incinerate Tyranids.
6. A Battle Against Time
The Flesh Tearers, led by Gabriel Seth, mount a desperate last stand against the Tyranids while they wait for a signal from the Solariam Crawler.
7. Of Monsters and Machines
In this battle Necron forces take on the Tyranids in low orbit around Aeros in order to secure the vapour-conveyer, which would allow the solar array’s attack to properly reach the planet’s core.
8. Forlorn Hope
In this final battle, Blood Angel forces fight their way through countless Tyranid swarms to reach the Magnovitrium’s activation mechanism on Tortoros, firing it off and ending the war.

Other Rules
The 7th edition update for Codex: Blood Angels would drop around the same time as Exterminatus, in December 2014. With the Codex Games Workshop would release a number of new kits for the Blood Angels. Specifically, the Terminator Librarian, Terminator Assault Squad, Karlaen, the Sanguinary Priest, Blood Angels Tactical Squad, and teh Death Company Chaplain (the really sick one with the winged jump pack), and a Blood Angels upgrade sprue.
The rules in Exterminatus focus on adding new formations for these models – the Archangels Orbital Intervention Force is a Detachment made from 3 Terminator or Terminator Assault Squads. Meanwhile, the Archangels Demi-company focuses on taking half of the first company and The Archangels formation is just the entire first company, with ten squads of Terminators or Veterans, four Furioso Dreadnoughts, a Captain, and a Chaplain.
In addition to these rules, the book also has rules for the Flesh Tearers and early rules for Necrons in seventh edition, giving players a Mephrit Dynasty Detachment they can use and new Decurion formations to field.
Final Thoughts
Shield of Baal marked the second of nine major campaign book events in seventh edition, each of which would feature Space Marines in some capacity or another. It would also mark the last campaign to use this naming scheme: the following release, War Zone Damocles: Mont’ka, would change things up to use the “War Zone” designation, in a similar fashion to the sixth edition Apocalypse campaign supplements.
The most notable event in Exterminatus is the alliance between the Necrons and the Blood Angels. This wasn’t the first time such an alliance had been described in the lore; the fifth edition version of Codex: Blood Angels also featured a temporary alliance between the two forces to take on Tyranids, with Dante and the Silent King putting side hostilities for a time to fight off a Tyranid splinter fleet. This is directly referenced in the book, and partly the reason for Dante ordering his men to stand down when approached by Anrakyr. The notion of Space Marines putting aside hostilities to team up with Necrons has always rubbed some fans the wrong way, and it certainly wouldn’t fly for a chapter like the Black Templars.
That said, if you had a nickel for every time the Blood Angels teamed up with the Necrons to fight Tyranids, you’d now have two nickels, and that seems like a lot.
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