Battle of Eagle Gate
To Kor Megron and his Word Bearers warband, known as The Foresworn, defiling the Shrine World of Eydolim was one of their greatest desires. Before turning to the powers of Chaos, they had discovered the planet and erected great cathedrals in the Emperor's service during the Great Crusade. In preparation for their grand offensive against the planet, Kor Megron sought out alliances with other Chaos Space Marine warbands. He succeeded in recruiting forces from Sons of Damnation, Corpsemakers, Night Lords, Red Corsairs, Iron Warriors, and Gladiator Group 138, bolstering his initial force of 200 Word Bearers to many hundred. He also acquired the aid of the Legio Excruciatus and Legio Interfector, two Traitor Titan Legions. With his new allies in hand, Kor Megron set out for the Eydolim System.
The first assault Kor Megron and his allies undertook was against the Hive World of Jones Crispin World. With his fleet quickly entering orbit, the Chaos forces took the Imperial defenders by surprise. The World Eaters of Gladiator Group 138 led the assault against the largest Hive, Fort Crispin, massacring all in their path. Frantic pleas for aid were sent out by the worlds Astropaths, and a force of Imperial Fists responded to the call, having been deployed nearby to combat the Tau Empire. The Imperial Fists and World Eater forces battled for weeks in bloody trench warfare around Fort Crispin. The Imperial Fists became bogged down in the fighting and were unable to aid any other world in the system, which soon also came under Chaos assault.
With the Imperial Fists tied down at Fort Crispin, Kor Megron moved his forces against other targets. The Red Corsairs moved against the orbital mines around the great gas giant Greater Eydolim. Nearby Adeptus Mechanicus Skitarii Regiments from the nearby world of Lector's Lowel were dispatched to aid the defenders, but were wiped out when the raiders detonated the gas depots in the mines. The explosion was so great that it was viewed half a system away. Lector's Lowel itself soon came under attack by the Iron Warriors and Red Corsairs who were backed by a Warlord Titan of the Legio Interfector. Against this force, thet Skitarii defenders stood little chance. It soon became apparently that Eydolim itself was next to feel the wrath of Chaos and the worlds defenders scrambled to make preparations.
Eydolim soon received aid from Crusade Group Black Gate, a force of Imperial Guard Regiments and Imperial Navy warships that had been deployed to reinforce the Damocles Gulf. The Crusade Group included 9 Cadian Regiments as well as smaller forces of Ventan Heavy Infantry, Vostroyan Firstborn, Valhallan Ice Warriors, and a company of Orn's World Militia. This greatly bolstered the undermanned PDF of the planet Days passed as the Imperial Navy battled the Strike Cruisers of the Chaos Space Marine fleets and the people of Eydolim huddled into their cathedrals and prayed earnestly for deliverance while the Imperial Guard and PDF forces dug in under the overall command of Cadian General Steinhold. As invasion neared, Steinhold prepared his men for the inevitably storm.
The Battle Begins
A week before the assault on Eydolim began, all communication with the Imperial Navy task force in the system was lost. Leading the Chaos squadron of Cruisers was the Black Legion Battle Barge Horn of Damnation. Bulk landers brought the heretic forces to land, harried by defense lasers and Thunderbolt fighters, but the Black Legion troops of the Corpsemakers quickly established a bridgehead on the planets surface. Chaos Hell Blade and Hell Talon fighters were deployed to wrench air superiority away from the Imperial Navy squadrons on the planet. The Word Bearers, operating from 3 Frigates, followed in kind. As soon as they made planetfall in their gigantic bulk-lander, they were assaulted by desperate Cadian and PDF forces. The result was that in less than an hour, 10,000 PDF and an entire Regiment of Cadian Shock Troopers were slaughtered by the Word Bearers. Together, the Word Bearer and Black Legion forces forged onwards towards Eydolim's capital city of Eydol as Red Corsair and Night Lord reinforcements landed at the conquered bridgeheads.
Though utterly outmatched, General Steinhold fought on. He used the Company Knights of Cadia to hold back the Chaos Space Marine advance for several hours at Hythe Ridge, though they were eventually driven back after a frenzied charge of Chaos Dreadnoughts and Defilers. After taking Hythe Ridge, the Chaos forces had acquired the valuable Promethium reserves. Meanwhile at Arabesque Station, a team of Kasrkin deployed by Valkyrie gunships attempted to ambush the Word Bearer command element. However before even half of the strike team had disembarked, Hell Talon fighters had blasted through their formation and destroyed most of their Valkyries. Only a few Kasrkin, led by Colonel Meere, escaped the debacle. Meere's forces even managed to fight on and destroy a number of Word Bearer vehicles before fleeing into the hinterland and waging guerrilla warfare. But despite their losses, the heroism of Imperial Guard forces on Eydolim was astonishing as the Chaos Forces continued to advance. Soon, Word Bearer forces were less then a day from Eydol itself.
The Spear of Sicarius
Meanwhile, the Ultramarines 2nd Company under Captain Cato Sicarius as well as a small force of 1st Company Terminators, fresh from fighting against the Tau, were diverted by Marneus Calgar to Eydolim to aid the desperate Imperial defenders. Deploying from the Strike Cruiser Valin's Revenge, the Ultramarines rapidly deployed at the outer walls of Eydol. The first contact between the Ultramarines and Chaos Forces occurred when a small Devastator task force assault advanced elements of the Legio Interfector, successfully destroying a Chaos Reaver Titan and crippling another two Reavers in an astonishingly successful ambush. Meanwhile, the battle for the outer walls of Eydol, known as 'The Eagle Gate', was underway. While Chaos Titans hammered through the Imperial force's left flank along the Eagle Gate, a force of Khornate Daemons were summoned by the Word Bearers and swarmed over the Imperial's right flank. The Chaos Space Marine forces took a more direct route, storming straight into the center of the Eagle Gate itself. World Eater Terminators from Gladiator Group 138 tore its way into the fray while Kor Megron and his Word Bearer retinue tore through a part of the wall and faced down the heavy guns and Leman Russ Tanks of the Cadian defenders. Despite this overwhelming assault, the Ultramarines and Cadians stood firm. Meanwhile, Cato Sicarius himself defended his heavy defended but shrinking position at The Gate of Martyrs against a sea of heretics and Daemons, waiting for the right chance to spring a furious counterattack. Another detachment of Ultramarines attempted to hold back a Black Legion advance on Martyr Street.
It was however at this point that the tide began to turn when Ultramarine forces halted the advanced of Word Bearer forces at the Gate of Martyrs, the Eastern entrance to the city. Kor Megron himself hurled into the action against Cato Sicarius. The two leaders engaged in single combat, with Kor Megron crushing the captain. However a nearby Imperial Guardsman heroically attacked the Daemon Prince with a mere bayonet, being quickly dispatched by the Daemon's warpflame attack. However the distraction was all the Ultramarines Captain needed, and Sicarius jammed his blade through the breastplate of the Daemon Prince. Kor Megron was dragged into the Warp, and the tide of the battle turned dramatically. Stunned and without their leader, the Word Bearers fell back. This was soon followed by their less numerous allies. Against all odds, the Imperial defenders had proved victorious, in no small part thanks to the heroic sacrifice of the lone unknown Guardsman.