Devastation of Baal

The Devastation of Baal (First iteration)
Date	~999.M41
Scale	Planetary
Theatre	Third Tyrannic War
Status	Inconclusive*
Belligerents
Tyranids	The Imperium of Man
Commanders and Leaders
The Swarmlord	Dante, Gabriel Seth, Ercon, Scaraban, Erden Cleeve, Follordark, Sentor Jool, Kaan, Raxiatel, Zedrenael, Zargo, Sendroth, Hajjin, Quaeston, and later Roboute Guilliman
Strength
Hive Fleet Leviathan	Blood Angels, Flesh Tearers, Knights of Blood, Blood Drinkers, Carmine Blades, Angels Encarmine, Angels Excelsis, Blood Swords, Sable Brotherhood, Angels of Light, Flesh Eaters, Charnel Guard, Golden Sons, Angels Penitent, Sanguine Host, Angels Glorious, Burning Blood, Brothers of Jarad, Blood Wings, and Angels Vermillion Space Marine Chapters, Legion of the Damned, and later forces from the Indomitus Crusade
Losses
Very high	Massive; see below
Outcome
*Battle is interrupted by the formation of the Great Rift

The Devastation of Baal was a gigantic three-way free-for-all battle between the Imperium of Man, Tyranids, and (later) a whole fuckton of Daemons for control of Baal and its two moons. It was one of the most calamitous events of the Third Tyrannic War for all parties involved, and was directly affected by the galaxy-changing Noctis Aeterna.

Prelude

The Cryptus Campaign

In 998.M41, the Blood Angels led a spirited defense of the Cryptus System during a grueling campaign against the onslaught of Hive Fleet Leviathan. With the reputable defenses of the Cryptan Shield having been severely fucked by the Hive Fleet, Chapter Master Dante quickly gathered an alliance of his own chapter, the Flesh Tearers Chapter, dozens of Imperial Guard regiments, the Order of the Sacred Rose, an entire Imperial Navy Battlefleet, and even a force of Tempestus Scions. Despite this massive Imperial presence, the Cryptus System fell anyways in just two days. In the ensuing Imperial counterattack, Dante forged an alliance with none other than the Necrons of Anrakyr the Traveller, who happened to have been in the system awakening legions of the Mephrit Dynasty. Who the hell let Ward get his hands on this narrative!? Together, the Blood Angels and the Necrons managed to activate an ancient Necrontyr doomsday weapon called the Magnovitrium, which ignited the core of the gas giant Aeros to send a massive pillar of flame across the system, incinerating the Tyranid fleet as well as some unfortunate Imperial soldiers, citizens, Sisters of Battle, and Space Marines (of course, the Necrons phased out right before the weapon activated). With Hive Fleet Leviathan having been dealt a huge blow, as well as all of the biomass in the Cryptus System having been burnt to a cinder, the Imperial forces (or what was left of them) withdrew. However, the Cryptus Campaign only delayed Leviathan's inevitable advance towards Baal.

Imperial Preparations

Realizing the incoming threat, Dante forged yet another alliance of Imperial forces. This time, he gathered the support of all 20 Blood Angels Successor Chapters, barring the Lamenters (you can't hold it against those poor bastards; by this point they're severely mauled, and they couldn't reach Baal in time even if they were still surviving to begin with). Even the renegade Knights of Blood Chapter answered the call for aid, but they wisely decided to fight separately from their brethren. Dante launched pre-emptive attacks against Leviathan, and managed to inflict losses against hundreds of splinter fleets. When the main Hive Fleet reached Baal, a mixed fleet of the assembled Chapters' Battle Barges and cruisers launched salvos of nuclear-tipped warheads directly into the mass of organic ships, causing extensive losses amongst the vanguard of the Tyranid onslaught. But eventually, all of the Space Marines' vessels were overwhelmed by the sheer amount of Hive Ships filling the space around Baal and its moons, and the Imperial forces on the ground could only watch as millions of living missiles began raining down on them past the wreckage of once-mighty Imperial ships.

The Battle

The Tyranids sent nineteen waves of merciless attacks, with each one being even larger than the last. These waves were driven off at great cost by the Imperial forces, with five Chapter Masters falling in these battles; three of the Chapter Masters were killed in the bloody Battle at the Dome of Angels alone. The Space Marines initially held their own thanks to recommissioning all of their powerful Heresy-era fortifications and weaponry, but the tide inevitably began to turn when the Swarmlord itself began leading the Tyranid hordes. Despite sustaining horrific wounds, Dante managed to slay the Swarmlord in an epic duel. Eventually though, as Baal itself was overwhelmed, the Tyranids began the process of draining the world and her moons of biomass, absorbing even the rad-poisoned desert of Baal Secundus. With the Imperial defenses falling little by little, the battered defenders retreated to the Blood Angels' Fortress-Monastery, with the planet close to destruction. But then...

The Devastation of Baal (Second iteration)
Date	~999.M41
Scale	Planetary
Theatre	Third Tyrannic War
Status	Imperial Pyrrhic victory*
Belligerents
Chaos	Tyranids
Commanders and Leaders
Ka'bandha	The Swarmlord
Strength
Hordes of Khornate Daemons	Hive Fleet Leviathan
Losses
All killed or retreated back into the Warp	Near-total annihilation
Outcome
*Imperium claims victory with the mutual destruction of the Tyranids and Daemons; Baal and its moons are almost completely devastated

Daemon Ex Machina

It was at this moment that the Great Rift opened up like a massive black scar across the width of the galaxy, and a ravenous horde of Khornate Daemons surged onto the battlefield. They were led by none other than the Bloodthirster Ka'bandha, the archenemy of the Blood Angels and their late Primarch. In a voice that probably sounded like Satan gurgling melted iron and the souls of the damned, he declared to the Tyranids that only he had the right to destroy his hated foes. Probably pissed off even more than usual at this point since the Tyranids didn’t understand nor give a fuck about what he just said, Ka'bandha and his groupies surged in and began slaughtering Tyranids and Imperial defenders alike on Baal Prime. With the planet and its two moons now cut off from the greater Imperium, and with two absolutely insane combatants dunking it out on a planet covered with corpses, Dante and Chapter Master Gabriel Seth of the Flesh Tearers had no choice but to evacuate with any survivors. Their forces were only able to escape due to the bloodlust-fueled sacrifice of the Knights of Blood, who all gave in to the Black Rage and charged directly into the melee of xenos and Daemon, probably blaring hard metal from their voxes and screaming obscenities towards everything in their path. The last thing Seth and Dante saw before the ramps on their ships closed were their renegade brothers selling their lives in one last act of heroic badassery.

You’ve Heard This Part Before

Lo and behold, at the most dire moment for the Imperial forces, who else would show up but Papa Smurf himself, at the head of his merry little Indomitus Crusade. With Rowboat Gullible and his allies forcing their way into the fray, the tides of battle began to change in favor of the Imperium. Adding to the strain on the Tyranids was the fact that the Great Rift happened to swallow a huge chunk of the Hive Ships stationed in orbit, leaving their ground forces stranded and leaderless. Of course, this did nothing to stop the Tyranids from fighting until the very end, and Baal was finally liberated only after a whole mess of battles. All of the Daemons either died under the guns of the Imperial reinforcements or fell back to the Warp. Ka’bandha, being the Daemonic yandere that he was, left a little gift for the Blood Angels in the form of his name on the now-barren rock of Baal Prime, formed from the skulls of hundreds of millions of Tyranid bio-organisms; it was the only trace the Imperials ever found of Hive Fleet Leviathan.

The Aftermath

With both Baal and its moons now thoroughly fucked (well, the moons were just fucked more than they already were), Guilliman and his allies immediately got to work helping his red-armored comrades rebuild their shattered home. Once they did what they could recovering from such a disastrous battle, the Blood Angels and their remaining Successor Chapters quickly set off to other Imperial warzones that were in desperate need of assistance, vowing to mourn their lost brothers at a later time. Speaking of which...

The Cost of Victory

This is a complete list of all the Imperial casualties of the complete battle, including losses incurred during the Cryptus Campaign. They will be sorely missed.

• Battlefleet Cryptus (all ships lost in the Cryptus Campaign)
• General Maelon Dhrost of the Imperial Guard (MIA, presumed dead on Asphodex)
• Millions of Imperial Guardsmen WIA, MIA, or KIA in the Cryptus Campaign
• Canoness Magda Grace of the Order of the Sacred Rose (KIA by a Tyranid Lictor on Lysios)
• Hundreds of Sisters of Battle from the Order of the Sacred Rose KIA in the Cryptus Campaign
• Commander Dante of the Blood Angels (WIA fighting the Swarmlord)
• More than half of the Blood Angels Chapter KIA
• 600+ Flesh Tearers Space Marines KIA
• Sentor Jool, Firstblade of the Knights of Blood (KIA in single combat against Ka'bandha)
• Knights of Blood Chapter wiped out fighting Khornate Daemons
• Kaan, Firstblood of the Carmine Blades (KIA on Baal Secundus)
• Carmine Blades Chapter almost completely destroyed while defending the Astropathic Choir on Baal Secundus
• Castellan Zargo of the Angels Encarmine (KIA while defending the Blood Angels' Fortress Monastery)
• 2/3 of the Angels Encarmine Chapter destroyed
• Follordark, Chapter Master of the Angels Excelsis (KIA when his Battle Barge Essence Eternal was ripped apart by Tyranid Bio-Ships)
• Angels Excelsis Chapter wiped out in space combat with Hive Fleet Leviathan
• More than half of the Blood Swords Chapter KIA
• More than half of the Sable Brotherhood Chapter KIA
• More than half of the Angels of Light Chapter KIA
• Flesh Eaters Chapter almost completely destroyed
• Charnel Guard Chapter almost completely destroyed
• Erden Cleeve, Chapter Master of the Golden Sons (KIA)
• Golden Sons Chapter destroyed
• Angels Penitent Chapter destroyed
• Sanguine Host Chapter destroyed
• Angels Glorious Chapter destroyed
• Burning Blood Chapter destroyed
• Brothers of Jarad Chapter destroyed
• Blood Wings Chapter almost completely destroyed
• Several Companies of the Angels Vermillion Chapter wiped out
• Blood Drinkers Chapter almost completely destroyed
• All but 1 of the Sanguinary Guard KIA. That is, only 1 Sanguinary Guard out of all 20 Chapters survived.