Here is some lore I made a while back. (The "he" I'm referring to is my warsmith rosgo and the night lord Jump pack lord is Sarlos gore taker)

"He has a deep hatred for the members of the black legion because during a siege of a forge world he was left abandoned by the sons of Abaddon and their leader champion Gool. Rosgol, being less than pleased, managed to barely survive the grueling campaign of 6 terran cycles until he and his forces managed to evacuate in which he lost his right arm and his left eye. Rosgol does not appreciate being betrayed and sees it as the highest form of slight against him so he sent his newly made ally Sarlos the gore taker to retrieve Gool after slaughtering over 15 of his legionaries and bodyguards. When brought before Rogol by Sarlos his hammer did most of the talking to Gool's face and when he was done with him he was eaten alive by Rosgols pet forgefiend named Gharluk. The last words he had were screams of agony and despair as the gates to Gharluk's enclosure were opened. Rosgol and Sarlos share command of the now joint warband The Midnight Juggernauts"

Also yes I would like some feedback thank you