Primarch

Before teh emprah became a vegetable he had 20 sons,who actually were clones of some sorts.However 2 of them just dissapeared probably due to Eldrads dickery and only 18 were found. These 18 broke into two equal teams and had the galaxys biggest "who has the largest dick" (also known as the horus heresy) competition, in which the Emperor and his mastodonic inproportional penis won. WTF am i even telling you about stuff you should know check the lexicanum for details about this shit.