The Sims: The main series fits this trope to a T. A list of all the ways you can torment your Sims is too long for this wiki, but here are some favorites: you can lock your hapless Sims in a room and watch them starve to death, drown them in a pool because they can't get out without a ladder (3 allowed them to climb out on the sides, but if you cancel out the action that has them do this, they'll drown like normal), have them launch a firework or place a fire jet indoors and burn the house down, feed them to the Cow Plant, refuse access to the bathroom, spread a plague throughout the neighborhood, and more. And of course, there's custom content: things like usable guns, or seemingly harmless objects that can kill and/or torture in fun ways.
There were even posters promoting The Sims 3 that actively embraced this gameplay, with a Sim wondering why he was was doing these crazy things.
Continued in The Sims Medieval, though that game is a little less wide-open and a little more like an RPG, so killing your active Sim rarely helps you. You can still have your Sims be all manner of nasty to each other, with options like dueling to the death and sending them to the pit.
In SimAnimals, you get to watch over all sorts of little critters and make sure that they are all happy and healthy. Or you could throw them into each other, dangle helpless squirrels next to hungry bears, drop them in water, starve them, and make it rain on them. If an animal is unhappy enough, they'll even attack your hand.
SimCopter puts the player in control of an unwieldy helicopter with which you are expected to carry out various missions, many of which involve human cargo. Forcibly ejecting passengers from the aircraft at high altitude invokes a minor penalty for injuring a civilian, silently cancels their original dropoff destination and creates a new medevac mission conveniently located nearby. Completing this new mission gives a reward exceeding the penalty, making it profitable to injure passengers with inconvenient destinations and instead deliver them to the nearest hospital. (It also stops captured criminals from escaping every time you land to make another pick up.)
Evil Genius, Spiritual Successor to Dungeon Keeper, gives players a wide selection of ways to "Interrogate" (torture) enemy agents and tourists. It's not unheard of in some circles for players to subject female agents and tourists to the greenhouse in the lab. One of the objectives of the game even requires the player to put an uppity crime boss into a hilariously oversized mixer located in the chow hall.
Dozens of traps, some pretty simple, some very deadly, others just plain cool. Who doesn't love watching a jet of flame streak down a corridor and roast those pesky agents?
Interrogation of captured agents (or even your own minions) can be done in many ways.
The interrogation chair has the minion doing the interrogation take a few approaches, such as spinning them around, crashing spit-covered cymbals against their head, and making them watch the minion's pathetic dance moves.
The laboratory has seven different pieces of equipment you can use for torture. There's an inquisitive supercomputer, a spin on a big centrifuge, a dunk in the biotanks, being put through a virtual cyclone in the environment chamber, a pummeling with the impact stress analyzer, and the classic frying with a giant laser.
A few less-obvious methods include making the victim dodge bullets on the marksman firing range, squashing them in bookcases, and putting them through a big mixer.
The Evil Genius can kill a minion at any time to inspire the workforce.
One kind of cell you can research can kill its occupant without a minion having to do the work. Suffice it to say, once you first build them, you'll probably end up capturing agents just to watch them get killed by these cells again and again.
The traps offer a lot of opportunities for fun:
Use wind generators to blow agents around a dozen corners before smacking them into a wall.
Giant Magnet + Sawblades = dead agent.
Corridor full of pitfall traps set off by motion detectors.
The Venus Man Trap. The sign in front of the plant says "Do Not Feed." Do the agents read it? Nope.
A room full of beehive traps and motion sensors can work wonders for keeping agents locked up.
A room floored in pressure plates, with wind generators blowing away from the one entrance/exit. Once an agent teleports in through the ductwork, they'll get repeatedly bludgeoned against a wall until they (eventually…) leave a corpse. The corpse will attract more agents, etc. Slow, painful, and it "makes its own gravy".
The Super Agents cannot be killed through normal means. Of course, this means that until you get up to the missions for disposing of them you can torture them over and over again.
Then there are some of the missions. You don't necessarily have to club baby seals, randomly be a dick to the agencies, or set off the Cuban missile crisis. But the option is there.
Life And Death and its sequel, Life & Death II: The Brain are surgery simulators. Needless to say, you can do quite a bit of damage to a patient if you're not careful or you're feeling sadistic. For example, you can start cutting before you turn on the anesthetic gas, at which point the game will play an audio clip of a bloodcurling scream, and you will be taken out of the operating room and given a lecture by the doctor in charge.
Like the aforementioned Life & Death example, the Trauma Center series lends itself to certain abuses. While you can't make your patients scream in agony, there are an awful lot of intentional mistakes you can stack up before they die, like cutting fluffy bunny shapes into their pancreas or stitching "THIS TROPER WUZ HERE" across their brain. In fact, the easiest way to restart a mission that you know you're going to fail is equip the scalpel and tap the stylus/A button rapidly, racking up massive vital losses and death in mere seconds. There's also the perennial favorite of half-removing shards of glass and stabbing them in again, or the more passive method of simply watching the viruses go. Add this to the fact that a lot of your patients are kids and you start questioning whether the ESRB shouldn't have been a bit stricter with the rating...
Bizarrely, since any improper application of your medical tools results in a loss in patient health, you can do this with seemingly harmless objects such as bandages, even to patients who aren't in any immediate danger.
In California Games, flying seagulls were also a target during the Foot Bag contest. Hitting one landed you 1000 points. (Not a whole lot, but still, you were rewarded with some points and a funny message.)
In the original Tropico, the entire premise of the game is being a Dictator on a tropical island/Cuba Expy which can be anywhere from a Benevolent Dictatorship to one where you use the military to attempt to keep your poor peons in place with bad food, no real medicine, and so on. And of course various edicts you can slap down to see just how far you can push your poor citizens...
Tropico 2 is still worse though, since at least in 1 your peons can leave, but in 2 you are the Pirate King of a Pirate Isle, and since the pirates under you only work as, well, pirates, or guards and overseers, all of your labor is provided by, well, slaves that you kidnap from settlements, including the prosti...er...wenches that you use to keep your pirates entertained. Plus the aforementioned edicts. And the fact that one of the ways to keep your captives from revolting/escaping is by keeping them in abject terror...
Tropico 3! You can lock political prisoners up in gulags, or have them gunned down in the street! Intellectuals being annoying? Go on a book burning fest! Elections being demanded? Martial law! Want to be subtle? Have your secret police assassinate the target while they sleep! Rebels have planted a bomb in your factory? Let them blow it up! Court the religious faction, and have them declare a political enemy a heretic! Slash the wages across the island and force everyone except your power elite to live in hovels, and then ally with the US or USSR to cement your power base! And cruelest of all, put the ranches in the middle of town so everyone is constantly facing traffic jams and cattle droppings!
The RollerCoaster Tycoon games provide a tool which you can use to pick up your guests and put them anywhere in the park. Including dropping them into the water and drowning them. You can also deliberately build certain rides to crash in a horrible, fiery explosion.
In the first game, one of the pre-made coasters is a loop coaster that's supposed to seem like the car is going over the edge, but then it stops and goes backwards. You can increase the speed on the coaster, watching the cars fly off in a terrible wreck. The game shuts down the coaster for this. You can open it back up again. Repeat.
The third game removes the requirement of actually finishing a coaster you have built, so you can build a roller coaster that launches at 100 mph that points directly at a path full of guests. Unfortunately, the guest cannot die. It is quite entertaining to see them fly after being hit by a 300 lb. roller coaster car, though.
You can synchronize rollercoasters to launch with their neighbors. String a couple of rigged shuttle loop coasters together and wait untill every car is loaded with poor, unsuspecting cattle. Best. "Fireworks". Display. Ever.
Non-lethal cruelty can be just as fun, and also profitable. For instance, dragging your guests to an island with nothing but a drink stand and a bathroom that costs $20.
Start building a path underground. When guests start using it, delete the path.
Connect the exit of one nauseating ride directly to the entrance of a second, and vice versa (after plenty of people have gotten in line).
Allow a Merry-Go-Round to experience a breakdown that causes it to begin spinning wildly out of control, then delete the path leading to the exit so mechanics cannot reach it to fix it, then surround it with raised land and pave it over with paths, leaving the guests trapped in a pitch-black hell of endless perpetual spinning and sped up music for all eternity.
One of the cruelest examples of this in the games has to be Mr. Bones Wild Ride◊. This is what happens when you make an insanely long ride out of a very slow rollercoaster type. Even at the beginning it takes several in-game months to finish the ride, and even then the ride was still expanding. The full ride that resulted had the riders on it for an entire year of in-game time before they were allowed to leave, with Mr. Bones occasionally taunting them that they are there forever. And the worst part is? The exit path leads right back to a completely sealed off space with an entrance leading right back to the ride they came from.
Mr. Bones: "The ride never ends."
Despite it resulting in an instant Game Over, many Stunt Copter pilots preferred to drop the stuntman onto the horse or driver of the target haywagon. Well, they are more challenging targets!
Animal Crossing allows you to attack villagers with your net and axe (although the latter cannot be used to mutilate them and is actually rather hard to pull off because it has shorter range than the former, so you'll likely end up accidentally going into a conversation with themnote In Wild World, you can just tap your character with the stylus to make sure you swing and not talk.), which will of course cause them to become depressed or outraged. You can bury pitfall seeds for them to walk over and get stuck in (they'll become unstuck over time or if you talk to them). You can push them around by walking into them, which has the same effect as hitting them (but with less tears), and talk to them repeatedly so they get flustered. You can just dig holes around a villager to trap them until you go off-screen, or combine this with the only way out being over a pitfall. New Leaf also allows you to buy an inflatable hammer, whose sole purpose is to hit villagers or other players over the head.
The objective of the freeware Porrasturvat/Stair Dismount is to push a guy down a flight of stairs by choosing a body part, angles, and power. You're scored on how much damage you do to him.
Likewise with Spiritual SuccessorRekkaturvat/Truck Dismountnote available at the same page as Stair Dismount abov, in which you position two ramps and a guy on a truck, and manipulate other factors, in order to cause said guy to fall out and get run over by said truck. And again, you're scored based on how much damage you do to him.
Dwarf Fortress has this in spades. Kittens are butchered to make the game run faster. Magma is dumped on sieges so the player has less clean up later, "unfortunate accidents" befalling troublesome dwarves... The list goes on.
Black Comedy is a part of the game. Two of the most hilarious threads on the forum discuss inventions such as mermaid bone gathering (24 pages of "won't you just need a room with chained up mermaids that has 4/7 water and a door leading to the airdrowning room for the babies?") and "Dwarven Child Care" (25 pages worth of dwarven kids locked in and defending themselves from animals who go nuts from being stuffed in such small cells).
When ghosts were implemented, players took too many inventive methods of inflicting on their own dwarves variously miserable deaths and/or torturous lives guaranteed to drive them berserk, in order to get their ghosts to appear. To kill more dwarves.
The game is cruel all by itself. Goblins will stab your guard dogs in the spine and then run away, leaving them permanently paralysed (until the player butchers them in frustration). Goblins will stab your Dwarves in the spine and run away, with the same effect... except you can't (easily) mercy kill the crippled Dwarf and there is NO easy healing.
Which is nothing compared to what can happen if a Dwarf with a talent for bonecraft is Depressed, Angry or Sober and falls into fell mood. They will butcher the nearest Dwarf to make a bone artefact. The worst part? If the Dwarf is a female carrying a newborn baby, you will get a baby-bone artefact.
The real cruelty is the players relentless experimentation with weaponizing anything and everything the Dev puts into their hands. Ordinary armoured dwarven axemen are all very well, but with a little ingenuity (and a cold enough overworld) it's possible to build a trap that automatically drowns attackers, then seals them in ice (in case they are immune to drowning), then drops them 40 stories, sets them on fire and finally melts down their belongings to recycle into weaponry. Without the enemy ever seeing one of your defenders.
Interactive Buddy. So many possibilities; everything from punching him to pelting him with flaming bowling balls while he's trapped in a gravity vortex to shooting explosive missiles. You actually get rewarded with money for hurting him (or being nice, but where's the fun in that?) and can use the money to buy new ways to "interact" with him.
Tamagotchi. You can scold them, starve them (or go the other way and make them morbidly obese), let them lay around in their own waste... One popular Self-Imposed Challenge once you're sick of playing the normal way is to see how fast you can kill them off.
In the Harvest Moon series, opportunities are ripe for abuse of both your animals and your neighbors. You can attack your animals with your tools, making them hate you - and, sometimes, your fellow townspeople too! You can also force townies to take rotten food, garbage, weeds, and food they really hate. The ultimate dickishness, though, is probably in the Friends of Mineral Town and DS games, in which you can put a poisonous mushroom in a group stew and give the whole town food poisoning. (Do it in DS Cute with a level 99 mushroom, and you get a Nonstandard Game Over, presumably from murdering everyone.)
In fact, in More Friends of Mineral Town, when starting a new game, you attack the mayor, after which he says "stop hitting me," and you are prompted to either stop hitting him... or continue hitting him, with a farm tool of your choice. You can do this indefinitely; it has no effect on anything. Encouragingly, he has a unique response for each tool; for the sickle, "stop cutting me," for the watering can, "stop watering me," etc. I'm not kidding. You can keep doing this forever.
Also, in some later games, if you want to marry a character called the Witch Princess, you have to do any number of horrid things, including repeatedly killing your animals. Which she praises you for. What. (Notably, in the girl version, when you first encounter the mayor [same guy, despite being a different town—long story] you again attempt to hit him. He dodges, mentioning that he wouldn't fall for the same trick twice. Your dog proceeds to run up and attack him.)
In Island of Happieness and Sunshine Islands, Mark and Chelseanote the male and female player characters. Playing as one gender makes the other a marriage candidate respond to all gifts with the "likes" reaction, meaning nothing you give them will give you negative points. Meaning you can raise their love points by feeding them a steady stream of trash (rocks, sticks, weeds, failed cooking dishes, etc.).
In the Rune Factory spin-off series, it is possible to trigger a proposal event and then reject the girl in question. She loses all affection for you, but it is possible to break the heart of every marriageable girl in game. Repeatedly.
In the Squeal Rune Factory Frontier, you may have left you old life behind that you started in the first game, including any wife and kid you may have had, for added points if you chose a wife that follows you into the new game in the series you could marry her again (leaving the child from the first game still abandoned) or marry a completely different girl wile your apparent ex-wife just looks on.
This was actually conceived as part of the reason for the Creatures series—in the slightly paraphrased words of the creator, "Something a father would teach soccer to, and a complete bastard would torture mercilessly." You can be a merciless god indeed, and many Game Mods exist that will simply make life difficult for your creatures. At the same time, the complexity of the creature's AI and artificial life made some fans wonder ifthis is ethical.
To add detail, the third game presents possibly the most cruelty potential of all video games ever made. There is a machine that allows injecing any chemical in the creatures. This includes various toxins that may cause a lot of pain, birth defects to unborn creatures and a nasty case of death. One may even inflict the worst pain there is by directly injecting pain chemicals. Oh yes, and there is one creature type, Grendel, that is ugly, evil and aggressive - socially acceptable cruelty ensues. In addition to the chemical injector, there are various other machines of fun - airlocks, piranha pools with a trapdoor (right next to where the Grendels spawn!) and a genetic splicer that reduces two creatures into a single egg with a nice slicing sound. And for the more scientifically inclined, genetic manipulation allows some innocent creature to be made utterly repulsive by making it emit a Grendel stench.
The Nintendo 3DSAR Games aren't exactly simulations, but one of the unlockable shop items is a globe. You can operate it much the same way as the globe in the Wii's Weather Channel. However, you can also shoot at it as you would in other modes. Shoot it too many times, and it will start to glow red. Keep shooting it, and it explodes. After the smoke clears, you're told to "Look after our planet." On top of that, the globe disappears from the menu, and you have to buy it again. It's only one coin, but still.
In Privateer, you play as a freelance cargo pilot, and you can make money any way you damn well please, up to and including drug smuggling and slave trafficking. You can even tractor beam the pilots of the ships you just blew up into your cargo hold and sell them as slaves. WOW.
Spoony: It's that kind of freedom, that little personal touch of pointless cruelty that makes you feel like a real authentic space bastard!
In MechWarrior 3, you can abuse the helpless soldiers in enemy bases in a variety of ways, like stepping on them (keep in mind that your Mech weighs dozens of tons) complete with crunching sound and shriek, or shooting them with a weapon, like a large laser, SRMs, or an auto cannon (also keep in mind that all of the rounds for those weapons are as large, if not larger than the person, so this appropriately disintegrates them, turning them into a red cloud).
Princess Maker has several endings where you can send your poor little girl down the path of darkness. She can marry the prince of hell or be essentially sold off to a dragon prince for all you seem to care. As she gets older even though she's still a young teenager you can force her to work in a hostess bar. You can even do so while forcing her to wear something that would be risque at the beach. For extra evil you can send her adventuring with the possibility of losing and being RAPED and she has absolutely no choice in the matter.
In Zoo Tycoon you can do a number of horrible things to both your guests and your animals. An obvious example is blocking off the entrance/exit so your guests can't leave. Or set your animals (especially the dinosaurs) free and let them eat your guests. Release a dinosaur near a bathroom and it'll take off the top of the building and eat the guest inside!
Surgeon Simulator 2013 has you acting like a doctor. Of course, you can try cutting the ribs with a power drill, use lasers on their eyes, power drill the brain, and flip them off. There is also an achievement for killing the patient in 15 seconds.
Wolf allows you to start a fight with any pack member of the same sex for any reason. Even if you're the alpha, you can still pick a fight with your subordinates; in fact, it's a good idea to do this at least occasionally, lest the beta decide they can usurp you (though the idea is that you only growl at them until they submit and then return to neutral activities, rather than mercilessly attacking them). It also allows you to hunt any time, even if you're not hungry and have a carcass sitting under your nose (real wolves occasionally do this, too; it's called surplus killing).