Ruinarch

There are many ways to be evil. Choose from three overlord Archetypes - each one provides you with a different playstyle. Do you want to focus on sheer destruction or are you into a more subtle puppetmaster approach?

Slowly gain new powers by upgrading the Portal.
Continue to sinisterly interact with the world to produce Chaotic Energy. You gain permanent access to more heinous Powers by upgrading the Portal. Depending on map size - from small to extra large - one playthrough may be longer or shorter. But more villagers means more ways to combine your demonic skills!

You can experiment by combining destructive spells.
The easiest way to wipe out villagers is to simply cast powerful spells like Earthquakes, Lightning and more. But what happens when you hurl a meteor at a poisonous puddle? Poisonous meteor explosions, that's what! And that's just one of the many nefarious ways that you can combine elemental interactions.

You can afflict villagers with flaws.
Sure, you could just destroy the world with ice and fire, but the real fun begins when you meddle with villager lives to put them into compelling and tragic situations! Afflict an annoying husband with Unfaithfulness and then watch the fireworks once you tell his wife of his misdeeds.

You can spawn monsters to kidnap and harass villagers.
You can snatch or seize a roaming monster and then breed it in your Kennel. This will allow you to summon them as part of your monster parties. Create monster parties to snatch Villagers or raid Villages.

You can spread malicious info.
Your Beholder Structure allows you to spawn Eyes all over the world to gather information. You've seen a Knight steal a Shaman's Potion? Store it as an Intel and then tell the Shaman about it!

You can spread Plague.
Build the Biolab to afflict Villagers with Plague and summon Plagued Rats. Upgrade your plague with various nasty symptoms and improve its virulence. You can even make Plagued victims explode when they die!

You can torture people.
You can build a Prison and incarcerate villagers. If necessary, you can torture them in ridiculous ways to afflict them with random flaws. Perhaps someone will have mental anguish and become a Serial Killer when it gets back to its village?

You can brainwash folks into becoming cultists.
You can also try to brainwash your prisoners. If successful, it will return to its village as a secret cultist who will quietly worship and aid you.

You can start a zombie apocalypse.
You can also make the Plagued dead rise as zombies. Other villagers that they attack may also contract the virus. Soon, the entire village will be filled with nothing but shambling zombies.

You can make Vampires and Werewolves.
Afflict a Villager with Vampirism or Lycanthropy to turn them into denizens of the night. Watch as they terrorize their neighbors and spread the curse! You may eventually see the Village fight back and start hunting.