Hive Fleet Kraken - Genestealer Infestation: Thirty-nine solar days after the Icharran rebellion began, the Ultramarines' Battle Barge Octavius entered orbit above Ichar IV and deployed its Drop Pods. The planetary defences were largely inactive due to the damage to the power generators of Lomas and as such the Space Marines' landing casualties were light.The Space Marines secured the Astra Militarum's armouries and the Imperial governor's palace and fought off several poorly organised counterattacks, causing massive casualties among the Brotherhood's forces. Outside, the remaining Imperial Guard forces launched coordinated attacks to link up with the Ultramarines, using their Leman Russ main battle tanks as moving strongpoints and slowly, inevitably, the Brotherhood's lines bent back.More than 20 Veteran Marines in Terminator Armour from the Ultramarines' elite 1st Company teleported into the great Brotherhood cathedral in Lomas and destroyed the cathedral's defenders after Agmar sent a message to the Octavius via spy satellite. More guards appeared from side doors and a storm of lasbeams and autoshells ripped out, massacring many of the Brotherhood guards, but not before several of the Terminators were dragged down.The Terminators' single Heavy Flamer proved to be invaluable, its flames incinerating the unprotected assaulting forces. Yet some of the Brotherhood Neophytes were striking out with inhuman speed and terrible claws, indicating their xenos heritage.The Terminators then spread out and searched for the myriad of secret passages that they presumed existed beneath the Brotherhood cathedral. They soon found one under the altar, and the altar was quickly removed. As they moved down into the crypt, they heard the clattering of claws on stone. As the creatures jumped into the lights of the Ultramarines, they were identified as Genestealers.This showed the Inquisitor's belief that there was a Genestealer Cult at the heart of the Brotherhood's revolution to be correct. The battle began and raged for a long time. Hundreds of Genestealers died, piling up one on top of each other. Eventually, the horde's numbers were spent in their attack. Several Ultramarine Terminators had been killed as their armour was torn open by the inhumanly sharp claws of the Genestealers. The remainder of the Astartes moved further into the crypt without encountering more of the creatures.Deep beneath the city of Lomas they found a huge cavern where the huge and bloated great grandfather of the brood, the powerful Genestealer Patriarch, sat. As the Terminators approached, another horde of Genestealers intent on protecting their alien master attacked the Terminators from out of nowhere. Storm Bolters rang out, resulting in pure carnage.The company Librarian fought his way to the dais but the Patriarch used its psychic powers to attack the Space Marine psyker. A surge from the Astartes' psychic hood broke the spell and the Librarian forced his body out of the real world for an instant and then he reappeared, teleported onto the dais. The creature lashed out and blood and sparks flew from the Librarian, but the Patriarch easily parried the return blow.The Librarian called on his battle-brothers for assistance and the dais was swept with bolter fire. Some shells pierced the power armour of the Librarian but the Patriarch was also wounded. The Librarian used this opportunity to strike with his Force Axe, the Librarian's own psychic power behind the blow allowing the weapon to tear through the tough hide of the Patriarch.The Patriarch was dead, suddenly leaving the brood and the entire revolution leaderless and unconnected by the cult's Broodmind. The revolution felt the death of its leader and lost its impetus and cohesion. The remaining Terminators slew the rest of the Genestealers and the battles above slowly stopped as the revolutionaries could only retrench themselves and no longer act in a fully coordinated manner without the Patriarch's subtle psychic guidance over the cult.Small groups of Brotherhood Acolyte Hybrids and Neophyte Hybrids held their positions in bunkers and towers but were soon destroyed by the tanks and heavy fighting vehicles of the Astra Militarum.Ichar IV was back under the control of the Imperium and all remnants of the Genestealer Cult - the Genestealers, their hybrids, infected humans, cult members and traitors -- were ruthlessly wiped out. Inquisitor Agmar, leading the Ultramarines, methodically purged the planet, which eventually returned to normal.There were still questions that remained unanswered. One was the fate of the human leader of the Brotherhood, as his body was never found. The second was that the planet's astropaths had reported a shift in the Warp, distant still, but the oldest of the Astropaths had sensed the psychic call of the Genestealer Patriarch radiating out into space and felt the change in the Warp. He had sensed something vast and shadowy, a monstrous entity which had turned its attention towards Ichar IV -- Hive Fleet Kraken.