I have some headcanon about Grogar, that I think you’ll like.  
Obviously, I do hold all what was said in-show canon, with Grogar being the very first emperor of what would later be known as Equestria, father of monsters etc.
 
Taking place before the unification of the tribes, Grogar was a powerful archmage, self-appointed (I am on the fence if he had a tribe of his own, or a flock, so to speak), gifted enough with magic that he could tear apart reality with mere whim, toy with the line between life and death. Academic, so to speak. And very disinterested in what morality there was in taking apart creatures and “sewing” them back together into hybrid creatures. Manticores among few are his creation, as is Discord.
 
Though his creations, often sentient in some shape or form, didn’t exactly receive much interest from him after having been researched, and were quickly abandoned to fend for themselves (He would have called it “let them loose to conquer, pillage and devour”, they would have called it being thrown out unprepared). Nothing else mattered to Grogar than academic pursuit of magic. Many magical artifacts, creatures and even magical concepts were created or theorized by Grogar, and no magical field was off-limits to him, including necromancy.
 
After a considerable amount of tyranny, a group of unicorns, led by Gusty of Flutter Valley (later known as Gusty the Great) managed to hinder the ram enough to gain a form of peace in proto-Equestria. Due to this, unicorn tribe gained notoriety and status, hence why they tended to be rich by the time of the Unification of the Tribes, with Gusty’s direct descendant being Clover the Clever, hoofmaiden of Princess Platinum (though, Clover the Clever the 2nd was Star Swirl’s apprentice, not the first one).
 
Recluse even during his prime, perhaps he is hiding somewhere, focusing on his experiments…