Well, well, well, which army to do...
I'll just stick with my Necrons.
Dynasty: Dahk'ash
-Known for their brutality, martial nature, and the frigid aura that surrounds them. When the Dahk'ash marched to war, it was on the wings of carrion flights and with hordes of canoptek machinations. Where the Dahk'ash were found, there was war, ruin, and ice. Worlds withered into barren wastelands and armies froze in their steps wherever the Butcher's gaze fell. They conquered many systems and were the bane of any and all who faced them, but like many before them and many who would follow, the Butcher's never ending appetite for war stretched the forces of the Dahk'ash too thin and the ice broke. In the midst of a war that stretched through systems the Butcher and his legions were made to sleep, the outcome of the war was never truly decided.
Leadership:
-The Dahk'ash are led by a triarch called, 'The Frozen Court'. This consists of the Phaeron and his two most trusted advisors. Below them were once many Nemesors who commanded the Butcher's legions, now very few remain, and even fewer are awake.
The Frozen Court:
-Ahtanath, the Butcher, Phaeron of the Dahk'ash: The Butcher earned his title after returning from conquest draped in the helmets of slain champions, a cloak he still wears. As of current, Ahtanath has yet to awake from his cold sleep, what awoken forces there are are led by the other two members of his court. He was last seen having no lower jaw and numerous gnashes in his necrodermis, whether this is on purpose or due to a flaw in his reanimation subroutines is unknown.
-Daragok, the Carrion Lord: Daragok is as formidable a strategist as he is an opponent, it is for this reason he captains the Dahk'ash flag ship (Name Unknown) and commands the entire Dahk'ash fleet, often operating through other Nemesors. His potential is best met in void and aerial combat but when the Butcher takes to foot, Daragok is often seen with him. The current location of the Carrion Lord was unknown, but Necron Sentinels from the Kageros Dynasty recently have discovered his whereabouts on the outskirts of the Charadon System. Not much else is known for contact was lost very soon after arrival.
-Inetkarus, Canoptek Lord: Resembling more a heavily modified Overlord, Inetkarus is the chief scientist of the Dahk'ash and leader of its canoptek hordes. Tasked with creating constructs to retro-form conquered planets to better suit the Dahk'ash he has created several classes of beasts to carry out this work, among these creations number the Canoptek Aphids, Canoptek Locusts, Canoptek Mantises, and the lumbering Canoptek Goliaths. Although tasked with changing a planet, they can easily turn their efforts to war as well. If pict captures from a Kageros Sentinel are correct, Inetkarus is awake and working with Dagarok.
To what purpose these awakening legions are committing themselves too is unknown, but if history is any warning, it is best if they are dealt with before they can reclaim their strength.
This is all I have on them for now but I still have a lot in the works.