There is an old African proverb: "The child who is not embraced by the village will burn it down to feel its warmth". What does the fledgling Overlad do to the village of Nordberg as a child after being shunned by them? He launches a massive firework to incinerate their holiday tree. Thirteen years after being unfairly thrown to the Empire like a piece of meat, he then returns as the fully-grown and evilly-empowered Fourth Overlord and takes over the town by force with the help of the fireball-tossing Red Minions. It goes further if he follows the Destruction path and leaves the whole place desolate and deserted.
Mortis is a Minion with the special ability to revive deceased Minions. This makes sense, as he himself is a Blue Minion, which are known for reviving dead Minions (though they're mostly limited to the recently-deceased).
Sooooo... In order to prevent her son from turning to a life of evil, Rose opted to leave the Overlad in Nordberg. This is knowing that he had glowing eyes of doom and lightning shooting out of his fingers and that the town people were not likely to take kindly to someone so different from them. Is anyone surprised he went from being a picked-on child to a full-fledged Evil Overlord, more so than his father even?
The fact that she spent the next few decades helping the Glorious Empire, who is dedicated to persecuting all types and sources of magic either makes this worse, or maybe indicates she just didn't care about the kid.
She left her child in a backwater place with people that possess less brainpower than the Minions, and more importantly, in a place far away from most of the rest of civilization. She then went on to marry Marius, the right hand of the Emperor himself, and (supposedly) became leader (or maybe shared it with her new husband) of the Sentinels. This means she's likely on top of the chain of command and privy to everything they find. She might have even steered them away from Nordberg for as long as possible. After all, it took the Minions a few years even after returning to the Netherworld to find the Overlad.
At best, the Third Overlord was an Anti-Hero with a case of Pragmatic Villainy while his son meanwhile can become a Lawful Evil tyrant. Makes plenty of sense when you consider his mother is the strict, order-obsessed Rose. He's takes after his mother in the logical sense, while emulating and perhaps surpassing his father in the tactical sense.
Lawful Evil tyrant. Makes plenty of sense when you consider his mother is the strict, order-obsessed Rose. He's takes after his mother in the logical sense, while emulating and perhaps surpassing his father in the tactical sense.