Sometimes video game expansions, whether the bonus discs ‘90s PC gamers remember or the downloadable extras former ‘90s gamers complain about today, are just second helpings of the same meal. Occasionally they do something different though, pushing at the original game’s boundaries, filling gaps, or swapping its genre for something completely different.

Like when long-running TV shows do the musical episode or the one in black and white, they’re both refreshing changes and bizarre experiments that would probably never exist otherwise. These 10 are prime examples.

’Fallout: New Vegas’
Sometimes surviving in a post-apocalyptic wasteland is grim and serious business, and sometimes it involves mad scientist brains in jars straight out of Futurama stealing your internal organs.

“Old World Blues” turns Fallout: New Vegas into a 1950s B-movie where your brain is stolen and replaced with a computer by incompetent scientists who then lose the original. You have to track down your meat brain, along with your heart and spine, like a David Cronenberg remake of Wizard Of Oz. When you finally find it, your old brain argues against being put back in your head because it’s much safer in a jar than the skull of a video game protagonist. Fair point, really.

’Mortal Kombat’
The Mortal Kombat games’ main selling point is that they’re drenched in gore, with characters like Sub-Zero able to rip out his opponents’ spines. The other gore-drenched thing Mortal Kombat’s target audience loves is horror movies.

So it makes sense that the ninth Mortal Kombat let you buy Freddy Krueger as a bonus character. By the tenth they went all out, adding killers from Friday The 13th, Texas Chainsaw Massacre, Alien, and Predator. Presumably the Predator’s here because he’s mad at Sub-Zero ripping off his signature move.

’Far Cry 3’
The Far Cry games are loosely connected stories about tough men doing murders in exotic locations like war-torn Africa, Tibet, or the Stone Age. Far Cry 3 went a bit further when it was remodeled into science fiction as “Blood Dragon.”

It’s not a sci-fi future based on extrapolating trends from the present or anything boring like that. “Blood Dragon”’s setting is the year 2007 as seen in 1980s action movies, with cyborgs and dinosaurs that shoot lasers from their eyes. It makes a boring old tropical island with some leopards or whatever look pretty rubbish.

’Red Dead Redemption’
For years people played Grand Theft Auto and thought, “Wouldn’t be great if these streets full of pedestrians were full of zombies instead?” The series’ creators, Rockstar, didn’t grant that wish, but they did throw zombies into another of their popular games: Red Dead Redemption.

Cowboys and zombies turns out to be a better combo than Cowboys And Aliens, but “Undead Nightmare” also gives you sasquatches, chupacabras, the Four Horses of the Apocalypse, and a unicorn. Because at that point, why not?

’Borderlands 2’
What do the characters from ultraviolent shootybang games get up to when they’re not shooting? According to “Tiny Tina’s Assault On Dragon Keep”, they play Dungeons & Dragons (here renamed Bunkers & Badasses to pass a saving throw versus copyright).

Having survived the story of Borderlands 2 its heroes sit down to pretend to be wizards and warriors in a fantasy kingdom full of orcs and skeletons, although this being an ultraviolent shootybang game they defeat them with a shotgun that shoots swords, which then explode.

’Rock Band’
There are 1,692 songs you and your friends can download and play on plastic instruments in the Rock Band series. With that many there are going to be some questionable choices.

However you feel about the music of The Naked Brothers Band, the Spongebob Squarepants soundtrack, or Cartman from South Park’s version of‘ “Poker Face,” it’s hard to go past this song without a double-take. “Charlene (I’m Right Behind You)” by noted 1980s new wave sensation Stephen & The Colberts is a minute-and-a-half joke from The Colbert Report that lives on thanks to the Rock Band version given away for free on September 11, 2008.

’Sleeping Dogs’
Sleeping Dogs is an homage to the kind of Hong Kong action movies where undercover cops with two guns shoot a hundred people and somehow don’t get fired.

One of its add-ons lets you enter a fighting tournament on a mysterious island straight out of a Bruce Lee flick, which is a bit different. But “Nightmare In North Point” goes weirder, pitting you against an army of hopping Chinese vampires and ancient magic. It’s Big Trouble In Little Chinatown, but in Hong Kong.

’The Elder Scrolls IV: Oblivion’
As fantasy games go, Oblivion is pretty bland: European forests, pointy-eared elves, a character played by Sean Bean who might not live to the end, etc.

But “Shivering Isles” takes you away to a land ruled by the god of madness, split into halves named Dementia and Mania–one a haunted swamp and the other overgrown with giant fungus like something out of Alice In Wonderland. It’s a strange backdrop to stranger quests, as you’re tasked with protecting the mad god’s subjects from a rival who plans to wipe away this messy land. It doesn’t help that all those subjects are batshit insane.

’Goat Simulator’
Goat Simulator was already pretty odd. You know the bit in games where you ignore the plot and go round trashing the town instead? That’s the entire game and also you’re a goat.

In “GoatZ,” a parody of popular zombie game DayZ, you’re still a goat but that town is now full of the undead, and you have a weaponized gumball machine strapped to your back.

’Mass Effect 3’
The Mass Effect games are about playing spaceship captain daddy to a bratty crew, and while there’s shooting the best part is the relationships between the characters: romances, friendships, rivalries.

“Citadel” adds an interlude to the middle of Mass Effect 3 that brings its characters together for a cheery adventure that climaxes not with a space battle, but a party as blearily fun (and stressful to host) as the real thing. An island of peace in an ocean of strife, it’s an admission that what we really want is just a chance to chill with characters we like, and the 30 hours of shooting is secondary. That honesty might make it the weirdest of this whole bunch.

Jody Macgregor lives in Melbourne, Australia. He writes about games for PC Gamer, ZAM, and Rock, Paper Shotgun, and writes about music for The Big Issue, FasterLouder, and inthemix. He’s on Twitter at [@jodymacgregor](].

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