The Humble Villager that was just trying to stop random adventurers stealing all their stuff -- Gallifreya
It began with a lucky shot. Tur the Peasant had had enough of adventurers stealing her things, and hucked a rock at the armoured figure going through Tur's sacks of meagre belongings.
They must have been at 1HP, because they fell and discorporated, leaving their swag behind them.
Tur spent a moment, dumbstruck, looking at the loot. Then she swept it up. There was some actual Silvers in the loot and she knew she would have to protect herself. Starting with the Adventurer's old armour.
Most of the money went on better locks and gates for her hut. And repairs on the armour. But she was able to trade in the old, rusted sword and some random items for a new sword and a few lessons on how to use it.
Lessons she needed, because no sooner had she got back to tending her pigs, than another adventurer came. Slightly better equipped. Hungry for loot. And they had a dog. But they didn't know how to use the animal properly, and their loot became hers. And so did the dog.
She trained the beast to guard the house, and outfitted him with armour as well. No sense in letting a good asset get slaughtered. Tur laid more than a few traps along her property, too. Making sure no adventurers got to what little she had. The copper coins that used to be her only wealth meant the difference between life and death, come winter.
More adventurers came. More died, leaving her their wealth. Before the snows ended, she had enough to make a fortified wall around her farm, and a cadre of mercenaries to make certain they stayed away. And more traps, dogs, and warding spells than she could have believed. Now she had silvers and a few golds to guard. And the most protected pigs on the planet.
Of course, selling them was a problem. The adventurers came in parties, now, and saw the pigs as a resource for her growing complex and attempted to attack them. After five or so parties, Tur's pigs headed to market in guarded, armoured wagons.
And after a couple of years, Tur didn't need to raise pigs at all. Now she was guarding her golds against a constant stream of Adventurers. And they were carrying gems and magical jewellery that could protect Tur and her teams from the inevitable further onslaughts.
Before she knew it, she was somehow an Evil Overlord. It didn't make sense. She fed and housed and armed and healed her troops. She hired many of the disenfranchised peasants who had lost their farms from Adventurer predation.
Tur the HeroSlayer, who never attacked a kingdom. Tur the Wicked, who never set out to do evil.
She'd only wished to protect what was hers.