Tau and Space Marines sustain heavy losses on both sides. But when it seemed that it can't be worse, part of Hive-fleet Behemoth was spotted. And it directed toward A'mis. So, El'amis and Captain Sicarius decided to put everything on one bet and all available forces were called to fight. The battle lasted three bloody days, Necron Lords were not giving up. When it seemed that everything was lost, one of the Mantas in reparation on orbit achieved full combat readiness. Hunter Cadre stationing on orbit loaded into and deep striked at the rear of the enemy. It confused Necrons for a moment. And that moment was enough: all Necron Lords fell under sniper fire from Pathfinders' Rail Rifles. Hammerheads and XV88's destroyed monoliths and rest of Necron Warriors were blasted out by sub-munitions from Manta's Railguns. The threat from the Necrons have been resolved.
But there still was Tyranid menace. Tau and Ultramarines sent fleet to engage Hive-fleet in space and give ground forces more time to regroup and get ready. Marines' battle barge readied Orbital bombardment bombs, Tech-priests were blessing Space Marines' armor. Tau repaired Barracudas, Tigersharks, Hammerheads and battlesuits, healed injured Fire Warriors. So it's been seven days. And then Seeding Spores started to drop. The sky grew purple-red. There was no much of planet's own flora, so Tyranids were not as strong as usual. This will stop them before taking over the planet in a few days - probably just extend the process.
So that's History of A'mis and introduction to the recently launched campaign. Our (mine and my two friends') first campaign. We use my set of Planetary Empires, 8 tiles per player.