The Battle of Lion's Gate

The Battle of Lion's Gate
Date	M42
Scale	Planetary
Theatre	Terran Crusade
Status	Imperial Victory
Belligerents
Khorne Daemons	Adeptus Custodes Grey Knights Solar Auxillia Sisters of Silence Primaris Space Marines Imperial Fists
Commanders and Leaders
Unknown	Roboute Guilliman Trajann Valoris
Strength
8 Bloodthirsters and 88 cohorts	4000 Adeptus Custodes, 50 Grey Knights, unknown number of Sisters of Silence, remnants of the Terran Crusade, Imperial Fists, Primaris Space Marines
Losses
All Daemons banished	Unknown, but at least 2000 Custodes slain, including one of the serving Tribunes.
Outcome
Ascension of Roboute Guilliman as Regent of the Imperium, and the launch of the Indomitus Crusade.

"That was the moment when the old precept changed. We could no longer pretend, and we could no longer hide. Terra was not like those other worlds – its billions were not easily erased from history, and if we had slaughtered all those who saw the daemons cavort on that night we would have had an empty Palace and a silent Council chamber."

– Alexei Lev Tieron, on the Battle

The Battle of Lion's Gate or more commonly known as the Second Battle of Terra, was a massive surprise attack of Khorne's demonic cohorts on the Imperial Palace. This came in the aftermath of the 13th Black Crusade, and the arrival of the revived Primarch Roboute Guilliman and the battered remnants of his Terran Crusade from Luna.

Prior to the battle

The fall of Cadia and the formation of the Great Rift caused its share of madness throughout the Imperium, and Terra was NOT exempt from this. In the overcrowded cities across the Imperial Throneworld, starvation led to desperation, which made to fertile ground for Chaos cults to take root. Riots turned into full-scale insurrection, and there was little that the Custodes, Imperial Fists, or the assembled Guard on the planet could do to stem the tide.

And this was BEFORE the Daemons started to be summoned in, as Shield-Captain Valerian and his Grey Knights strike team found out first-hand.

The Bloody Gauntlet Thrown

Warp rifts opened across many of Terra's hive-cities, and from these streamed 88 Bloodletter cohorts led by 8 massive Bloodthirsters. They were tasked with one thing: take the throneworld and prove Khorne's superiority to the other Chaos powers.

Did we mention that it started raining blood through all of this? Metal.

Whatever Loyal Imperial forces weren't swallowed up by the daemons were pushed back against the walls of the Imperial Palace. Even with the mighty weapons emplacements raining down ruin on the daemon hordes, desperate battles erupted all across its base as those Custodes trapped outside the walls and the Grey Knights strike teams they led tried to stem back the tide. The surprise arrival of contingents of Sisters of Silence (including one Tanau Aleya), recalled by Trajann Valoris himself and flown in via Aquila landers from their orbital muster points, helped even the odds a bit for the defenders, but the daemons were seemingly endless.

Then for the first time in ten thousand years the Lion's Gate opened, and out of its depths charged out a full four thousand angry and oiled up Golden Banana-men, as well as their aircraft and support vehicles. The golden host struck hard at the red tide of Daemonkin, with the Captain-General himself leading the attack on the biggest Bloodthirster within striking distance.

With this sea of gold marched the proud remnants of Guilliman's crusade, with Bobby-G in the lead, followed likely by Saint Celestine, Belisarius Cawl, Cato Sicarius. Its was during this battle that the first of the Primaris Space Marines were awakened by Cawl, and it is here that they proved their worth.

The fighting was fierce, with even Big Blue forced into a mano-el-mano duel with a Bloodthirster on the ramparts, but after several hours of hard fighting the last daemon was banished back to the Warp. While the Imperial defenders won, the daemons left much uncertainty in their wake, and while the shattered defenses can be eventually rebuilt, the confidence of the High Lords of Terra in the homeworld's invincibility was no longer as ironclad.

Aftermath

Before the dust even settled, whole warbands of the Inquisition began scouring the surroundings of the Imperial Palace, and dealt with any lingering Chaos taint with extreme prejudice. The Sisters of Silence were given back their old strongholds, while Guilliman's rule as the Lord Commander and Regent of the Imperium was formalized.

Wary that the whole attack was one massive distraction, a whole Sodality of Custodes led by Valerian and about fifty Sisters of Silence went rogue, and made for the Fortress World of Vorlese. There they found the forces of the armless failure trying to close the stable warp points located there via corrupted Cadian Pylon shards. This plan was stymied, but at great cost, and by the time reinforcements found them, only Valerian, Tannau, and another Custode were the only ones left alive.

With his power base mostly secure, Guilliman announced the start of the Indomitus Crusade, centered on several legions worth of Primaris Space Marines. These fleets would spread from the Sol system to the segmentum beyond, and brought relief and reinforcement to embattled Imperial forces wherever they went.

Finally there was a little matter of the High Lords of Terra erupting in open rebellion against Guilliman, but Bobby-G planned for that too, and it was handled neatly without anyone the wiser for it, barring Trajann Valoris.

And what of Khorne and his daemon hosts? Well, he was SO pissed (much more than usual), that he obliterated the 8 Bloodthirsters where they stood. No more rebirth for those, thats for sure.