Battlefleet Bakka - Battle of Circe: Behind the two fleets the very fabric of space rippled before it was suddenly torn aside as another fleet emerged from Warpspace. The hologlobes were filled with ranks of red sparks as the second Tyranid Hive Fleet bore down on the warships of the combined Imperial fleet. This Hive Fleet was fresh and undamaged: hundreds of large bio-ships made up its vanguard with their smaller companions staying to the sides and rear. Calgar desperately sought an edge to exploit against this new foe. The other Hive Fleet had only been defeated because it was surprised and weakened; this new fleet was too strong to fight. The defences of Macragge were hours away, damaged by the ongoing Tyranid assault but still operational. The only other defensive point in the Macragge System was the ringed gas-giant Circe, which they could reach within the hour.Calgar headed back to Macragge. Lord Admiral Rath declared that too many of his warships would be caught before they reached that planet and turned away toward Circe. As the ponderous voidships of Battlefleet Tempestus swung their prows towards roiling Circe and its treacherous rings of rocks and dust, the Hive Fleet smoothly divided itself. The greater part of the alien bio-ships pursued the Imperial vessels towards the gas giant and its shining rings. The remainder dogged the Ultramar fleet with such numbers that to turn back would be suicidal. Amidst the rings of Circe the Imperial fleet turned at bay, their engines holding them at a dead halt above bands of planetary storm that reached about the giant's circumference. The Tyranid bio-ships swept forward in a wave which filled the monitors and gun sights with targets. Laser salvos and plasma beams struck down the bio-ships by tens and then hundreds but the Hive Fleet ground forward regardless of loss. Vessels of both sides fell towards Circe's hungry pull as they were hit, tumbling down to be smashed apart in the stony rings or to send flares of incandescent gas jetting into space as they burned amidst clouds below.One by one the Imperial vessels were grappled and overrun or torn apart by the hail of shots from a dozen foes. The rings flared with the bright flashes of Imperial ships dying in fiery wreaths of plasma. The skies above Circe were filled with the detritus of war, charred fragments of warships and bio-ships merging together to form new rings of steel, blood and bone. At the height of the battle only a fraction of the Imperial warships remained operational, amongst them the scarred bulk of the Battleship Dominus Astra. Giving his remaining ships a final order to scatter, Lord Admiral Rath swung the mighty capital ship about and thrust forward into the heart of the Hive Fleet. Roaring forward on its many tails of white fire, the Dominus Astra ripped through the bio-ships with its jagged ram, weapons blasting from every gun port and turret, the enemy so close that the shot and detonation of its Fusion Cannon were simultaneous. For a brief instant the Dominus Astra kept the horde back with the blaze of its weapons before the Tyranids swept in like a tide of bone and flesh to cover it with their numbers.A black globe crackled and flared into existence over the spot. Realspace rippled visibly and then shuddered back before the groaning warp drives of the Dominus Astra as it hurled itself into the Warp. Reality contorted under the strain: mass and Warp energy collided in a cataclysmic implosion of black light and impossible sound. All of the closest Tyranid bio-ships were dragged into the Astra's displacement and were lost with it. Those further away were smashed in the swirling storm of dust, rocks and other detritus swept into the ship's wake. Great flares of incandescent gas gouted up from Circe to incinerate the handful of surviving ships that remained in a holocaust of flame. The Dominus Astra disappeared into the Warp, never to be seen again. Only a dozen other ships of the proud Battlefeet Tempestus survived the Battle of Circe. These limped away towards Macragge, though the battle for the Ultramarines' homeworld would be long over by the time they arrived.The last stand of Battlefleet Ternpestus was visible on magnascope, the light from Circe's orbit taking seconds to catch up with the Ultramar fleet. Calgar could only helplessly watch the Imperial vessels wreathed in the flame of their weapon fire, the silent explosion of Tyranid bio-ships as they were struck, the glittering aurora of lights as laser salvos vaporised rings of dust. As the Dominus Astra dragged the heart of the Hive Fleet to oblivion, the bio-ships pursuing Calgar started to split up, the smaller vessels rushing after the Ultramar ships while their larger companions turned back and left the Macragge System. In space, the survivors of the Ultramar fleet easily destroyed the last wave of bio-ships. The Tyranids drove straight forward against the fleet and Macragge's defences, but each successive foe was destroyed before it came anywhere near the planet. Hive Fleet Behemoth had been defeated, but the cost was incalculable.