M30

It was in the middle of the millennium that 18 Primarchs were born, the birthing screams of the Empress and Slaanesh was psychically loud enough that all the Eldar in the galaxy had an aneurysm for centuries.

Half of them were born from the Empress' womb while the other half was born from Slaanesh's.

Felica (Fulgrim), Lyra Russ (Leman Russ), Selnagunineous (Sanguineous), Fura Raucous (Ferrus Manus), Mortaria (Mortorian), Magna the Red (Magnus), Cora Corax (Corvus Corax) and Aplarina Omega were born by Slaanesh.

Kola Cruza (Konrad Curze), Angra (Angron), Vulklna (Vulkan), Rafaella Gulimum(Roboute Guilliman), Taffy (Logar), Relga Dorn (Rogal Dorn), Rena El' Joan (Lion El' Johnson), Erta (Perturabo), Mahati Kahn (Jaghatai Kahn) and Whora Lupercal (Horus) were birthed by the Empress.

However, as soon as they were born they were snatched away by the Chaos gods and scattered across the stars. Slaanesh and the Empress screamed in rage before they set off to find their children and conquer the stars.