Minecraft in Elden Ring and TNT in RDR2: The Wild AI Mashups That Broke the Internet — What's Real and What You Can Download

In the last days of September, X turned into a parade of impossible crossovers. Steve from Minecraft flies over the capital of Elden Ring, Mario from Super Mario 64 triple-jumps away from Margit's swings, and in GTA 5 Steve holds off the cops and a tank with a diamond sword. In Red Dead Redemption 2, a block of Minecraft TNT sits in the middle of Valentine, while someone runs around Riverwood in Skyrim with a rocket launcher from Quake. The Elden Ring clip alone racked up 22.5 million views.

The captions promised magic: "AI hackers have put skateboarding in Call of Duty," "Claude managed to port Minecraft into RDR2," and some reposts went as far as claiming the games had been "fused from the code." In reality, these mashups are built by hobbyists working with AI models that write code, launch the game and fix their own bugs. The most popular trick works like this:

Some of these mods can be downloaded and played today. Others exist only as videos.

Steve in diamond armor flies over Leyndell in creative mode, fights the Lands Between's enemies with a Minecraft sword and bow, places blocks and digs through his inventory. According to the captions in the video, the mod includes creative mode and 1,600 items, and halfway through a Black Ops mode shows up with weapons from Call of Duty Zombies and a round counter. The clip was posted by Tobyn Jacobs, a San Diego artist previously known for giant paper figures, and it became the face of the whole wave.

Some viewers decided the video was edited. Jacobs replied with a phone recording of himself playing the mod on a laptop. For now it only runs on a Mac, even though Elden Ring was never officially released on Mac, and he hasn't explained how he runs it there.

Download: not available, the author hasn't released the mod.

Steve with a diamond sword and ender pearls against a five-star wanted level: police cars and a tank roll toward him. Creepers and TNT go off as real GTA explosions, crossbow fireworks hit like rockets, mobs hunt pedestrians and brawl with the cops, and a Nether portal turns the sky over Los Santos red. There is also an elytra flight over the city.

This is the showcase example from Universal Modder, an open-source toolkit by engineer Rehan Sheikh, and it is the best documented mashup of the bunch: the code is public, and the AI agent left detailed notes on its own work.

Download: there is no ready-made mod, only the source code on GitHub. You have to build it yourself, which is not a job for beginners.

Mario, with the health meter, coins and stars from Super Mario 64, takes on Margit, the Fell Omen: triple jumps, punches and the signature star burst at the end. Even the boss's name is redrawn in the Mario font. The clip by Deltaroo has 5 million views. The author doesn't say whether AI was involved.

Download: releases on the author's GitHub. You need your own Super Mario 64 file, and it only works offline.

Spider-Man from Marvel's Spider-Man Remastered web-swings over Gotham from Batman: Arkham Knight, crawls up walls and perches on ledges. Luki, the creator of the ArkWeb mod, is upfront about the bugs: buildings are sometimes hollow, and Spider-Man can look too dark because he is still lit as if he were in New York.

Download: source code on GitHub only. You'll have to build it yourself, and you need a controller and one specific version of Spider-Man.

SkyCraft by the modder chasm: Steve walks around Whiterun, TNT leaves craters in the tundra, block buildings are lit just like everything around them, and hitting a citizen counts as a crime. The mod is rough. A Kotaku writer tried it herself: breaking metal gates gave her wood, some blocks didn't render, and at one point she walked into an invisible wall.

Download: releases on GitHub, where the main archive has about 5,500 downloads. Windows only, and it needs roughly 3 GB of RAM on top of the game itself.

A soldier from the 2009 Modern Warfare 2 rides a skateboard, does kickflips and grinds rails that the mod finds on its own on any map. Later versions added a whole Minecraft world with mobs, TNT grenades and MW2 rifles. The short clip on X got 7.3 million views, and chasm also posted a detailed 12-minute video on YouTube.

Download: releases on GitHub, about 8,700 downloads. You need your own Steam copy of MW2. Skate 3 files from the Xbox 360 version are only needed for skate mode, and you don't need Minecraft installed: on first launch the mod downloads its files from Mojang's servers.

P.E. Cooper moved the classic zombies map from Call of Duty: World at War into a web browser. He says two AI models took the game apart and ported it: Anthropic's Opus 5.5 and Astra (most likely GPT-6 Astra, OpenAI's newest model). Along the way he hit his Codex usage limit a couple of times and his Claude limit once. Then he started goofing around: one clip has Mario racing around the zombies map in a kart, and in another a portal gun drops out of the mystery box. That one got 1.6 million views.

Download: not available.

It's called Escape from Skyrim. On September 29, a creator going by Cydonyx posted that he'd put Tarkov into Skyrim, and about 11 hours later he shared the video: the inventory from Escape from Tarkov laid over Skyrim, a rifle with a red dot sight and a firefight in Riverwood. He stresses that this isn't an overlay and that the models are actually in the Skyrim engine. Part two added an AKS-74U, and on October 1 he dropped Spider-Man into the same Skyrim. That video got 1.4 million views, more than the first one. He hasn't said whether AI helped.

Download: not available.

A TNT block in the middle of Valentine's muddy main street, a Minecraft bow against the townsfolk, a WANTED banner over Arthur Morgan, a lead on a horse and an elytra flight over town. The clip has 1.8 million views. The caption says "claude managed to port minecraft into RDR2," but the account has fewer than 150 followers, there's no code, and the post quotes someone else's compilation, so nobody knows who made it or how.

This is the chasm compilation: 3.8 million views and nine clips in a minute. Tommy Vercetti skates through GTA: Vice City, Jimmy from Bully boards around Bullworth, Minecraft hearts and a hotbar appear in the Kokiri Forest from The Legend of Zelda: Ocarina of Time, Sora from Kingdom Hearts fights in Borderlands, and someone runs around Riverwood with Quake's weapons and HUD. The Vice City Skate and BullySkate mods are on GitHub, while the creators of the Quake and Zelda clips are unknown: those clips don't appear anywhere except the compilation.

Modder Swirly also put all of Minecraft inside Super Mario 64, except he spent two months on it almost nonstop. "I guess super grok can do it in a weekend now or something," he joked in a post with 1.6 million views.

Download: not yet. Swirly promises a release and a technical breakdown.

On October 5, a video quickly went viral on X in which Elden Ring was suddenly transformed into a first-person shooter. The hero dashes through the gloomy world of Leyndell wielding guns and interfaces from various shooters, clinging to walls with a grappling hook, while the boss is monitored via cameras, just like in Five Nights at Freddy’s. In the finale, a combat robot appears on screen. The video’s caption lists eight games: in addition to Elden Ring itself, these include FNAF, Halo, Overwatch, Apex Legends, Titanfall 2, Tony Hawk’s Pro Skater 2, and DOOM. The video was posted by Overwatch streamer Huberticus, who captioned it: We’re almost at the peak. Within a few hours, the clip had racked up over 270,000 views. The author didn’t specify whether he created this mashup himself or if AI helped him—there’s no code.

Download: not available.

The whole wave grew out of a single Discord server in less than a week.

On September 27, chasm posted a clip of skateboarding in Modern Warfare 2, and plenty of people assumed it was AI-generated video. On September 29, Tobyn Jacobs showed off Minecraft in Elden Ring, and the floodgates opened: Mario vs. Margit, Tarkov in Skyrim, Call of Duty Zombies in a browser. On September 30, Rehan Sheikh released Universal Modder, and on October 1 chasm cut mashups from members of his Discord server (about 5,800 people) into a one-minute compilation.

None of the projects whose inner workings are known merged the code of two finished games into one program. Modders take a shortcut instead. Most often both games simply run at the same time and pass data back and forth. Less often, one of them gets rewritten from scratch.

This is how Minecraft in GTA 5 and Skyrim, Spider-Man in Gotham and Kingdom Hearts in Borderlands were made. Both games run on one PC, each with its own mod, and a bridge sends data between them every frame. Well-known Roblox developer Max called the trick "a really clever shortcut" and "pretty cheeky." Here is how it works in GTA 5:

The setup has clear limits. GTA treats every placed block as an invisible obstacle, and once these objects, together with everything else the mod spawns, reach about 1,500, the game crashes. That is why you can only place 400 blocks. Steve can hold GTA weapons only in an experimental mode that looks bad, so in the videos he fights with a sword and a crossbow. ArkWeb pulls an even funnier trick: the Spider-Man game runs in the background and sends over its image, while Batman becomes an invisible puppet that copies every move Spider-Man makes, so Arkham Knight knows where the hero is.

The idea is older than AI. Back in 2021, the Crusader Blade mod linked Crusader Kings 3 and Mount & Blade 2: Bannerlord: armies from the strategy game fought their battles in Bannerlord, and the result went back into the campaign. The mod came back this September, and it still needs both games running.

This is how Mario got into Elden Ring, and the trick is years old. Fans long ago took Super Mario 64 apart down to the last line of code and pulled out Mario himself, complete with his jumps and physics. That ready-made Mario can be dropped into any game: Elden Ring tells him where the floor and walls are and which buttons the player is pressing, and he runs and jumps exactly like in the original. Long before this wave, the same Mario showed up in Garry's Mod.

Skateboarding in Modern Warfare 2 isn't a mod at all. A developer known as vladtrc rewrote the 2009 shooter from scratch: the new program loads maps, models and sounds from your copy of MW2 and does everything else itself. chasm bolted on a rebuilt version of Skate 3's skating and a homemade Minecraft, and it all runs as a single game. Skateboarding in Vice City, a game fans rewrote from scratch long ago, belongs to the same family, and so does skateboarding in World of Warcraft, for which hobbyists rewrote the entire game client. Bully is simpler: it's a regular mod for the installed game that brings in the same rebuilt Skate 3 skating. This is the slowest route. chasm says the code was almost entirely written by AI, but he spent weeks polishing the Minecraft part by hand because the AI couldn't tell whether it felt good to play.

You can also bring over a single thing, like an enemy or a weapon, by rebuilding it inside another game with that game's own modding tools. That is how Tobyn Jacobs got creepers into Dark Souls back on September 25, and he wrote himself that Claude on Opus 5.5 made them. P.E. Cooper says he moved the whole World at War zombies map into a browser: the AI models took the game apart and rebuilt the map, though he hasn't gone into detail.

Nobody knows. A few hours before the clip, Jacobs showed that he works with several models at once: DeepSeek V4 Pro, Opus 5.5 and Astra. Universal Modder's notes credit the clip to Claude, but they don't describe the method, and the author hasn't published any code. After the wave, another developer released an open-source take on the idea for Mac and credited Jacobs with it.

AI took on the most tedious part: figuring out someone else's code, writing the bridge, launching the game a hundred times and checking that it doesn't crash. Coming up with the idea and judging whether the result is any fun is still a human's job.

People work with these models through AI coding agents such as Anthropic's Claude Code or OpenAI's Codex. Claude Opus 5.5 is the name you see most often in this wave: it is credited in the commit histories of SkyCraft, the MW2 skate mashup and ArkWeb, and Kotaku calls SkyCraft a "Claude-coded" mod. Other models are in the mix too: P.E. Cooper used Opus 5.5 and Astra and kept running into Codex limits, and Jacobs's lineup also includes DeepSeek.

Minecraft in GTA 5 shows best how long this kind of work actually takes. The agent's field notes describe about two days of Claude Code sessions with one person, who set the tasks and handled what the agent isn't allowed to touch. On X, Rehan talks about "a few prompts." The agent wrote most of the code before the 125 GB GTA install had even finished, testing it against a homemade dummy that pretended to be GTA. At one point an agent script switched to the game window while the human was typing in another one, the keystrokes landed in the start menu, and GTA nearly went into GTA Online with mods loaded. The main GTA mod loader saved the day: it refuses to let the game go online, where modding gets you banned.

The speed is impressive. Tarkov in Skyrim appeared in 11 hours. Former Epic Games employee Aakash Gupta wrote about the MW2 skate mod that a studio team usually spends multiple quarters on a traversal system like that, while the project had only 31 commits when he posted. But there's also Swirly with two months of handwork and chasm himself, who spent weeks polishing Minecraft by hand. AI has drastically shortened the road to a working prototype, but it can't yet turn a prototype into a game.

Universal Modder also has a business angle. Rehan Sheikh used to be CTO of the startup Remade AI, which was bought by fal, and he now works at fal as an engineer. His toolkit generates sprites, 3D models and sound through fal's paid service, although the GTA mashup didn't need any new art at all. Every finished example in the toolkit was made in Claude Code, while support for Codex, Cursor and Gemini CLI is so far only announced. Under the launch post, which has 3.6 million views, X users added a Community Note: the promo video was stitched together from other people's mods, including Minecraft in Elden Ring and battles from Pokémon Emerald, and only the Terraria and Age of Empires II footage was made with the toolkit. Rehan replied that he had credited all the creators.

Only a handful are playable, and only on PC: none of these mods exist on PS5, Xbox or Switch.

Keep the risks in mind before installing anything:

If you want to build a mashup of your own, start with our guide on how to mod almost any game with Claude Code. You'll need an AI coding agent, usually on a paid subscription, and a few free days.

Myths grew around these clips almost as fast as the clips themselves.

One viral repost put it this way: "This is NOT a mod. They literally fused RDR2 and Minecraft from the code." There's no evidence of that: the creators of the RDR2 clip and of Minecraft in Elden Ring haven't revealed how they were made. Where the inner workings are known, these are mods, two of them, one for each game, plus a bridge in between: that's how Minecraft in GTA 5 and Skyrim and Spider-Man in Gotham work. When everything really does run as one program, the game was either rewritten from scratch, like MW2, or given a ready-made hero from a long-decompiled game, like Mario.

It didn't. Rehan's toolkit produced Minecraft in GTA 5, the Terraria and Age of Empires II examples and the first user experiments. SkyCraft, the MW2 skate mod, Mario in Elden Ring and Spider-Man in Gotham are separate projects by other people, and how Minecraft in Elden Ring was made is still unknown.

Not any two. With the bridge setup, your PC runs both games at once, which is why the guest is almost always something light like Minecraft or Mario, and in the GTA example the Minecraft image was even capped in frame rate and resolution. The host games are ones with huge modding scenes and ready-made modding tools: GTA 5, Skyrim, Elden Ring. Online games with anti-cheat are ruled out from the start, since Universal Modder's rules forbid touching them.

A banking app doesn't work like a game on your PC. Balances and transfers live on the bank's servers, the app only shows the server's answers and sends requests, and the server re-checks every transaction. So you can't "decompile the app and fake transactions" by modifying it on your own phone: that won't create any money, just like a story mode mod won't put dollars into GTA Online, because those live on a server too.

That doesn't mean there's nothing to worry about. AI makes attackers' work cheaper, and they go after both people and the services themselves. In September, Group-IB described RemControl, an Android trojan that draws fake windows over banking apps, and one of its phishing pages still had a forgotten AI assistant reply on it. Anthropic's September report admits that its models, including Claude Code, were used in real attacks: they helped write and debug hacking tools, while the attacks themselves relied on stolen passwords, long-known holes and poorly protected services. In the company's assessment, AI has effectively erased the gap between state hacking groups and lone attackers. Back in February it emerged that a hacker had used Claude, and partly ChatGPT, to attack Mexican government agencies starting in December. Google described an attacker who harvested thousands of credentials in under six hours with a "team" of AI agents, and among the models abused by attackers it lists its own Gemini as well as Claude and Codex. Still, in the attacks covered by Anthropic's September report and OpenAI's October 2025 report, no fundamentally new hacking techniques turned up: AI made familiar attacks cheaper and faster.

There's no broad public response from publishers to the wave yet, but their track record shows that mashups featuring other companies' characters can disappear at any moment.

In September, Rockstar tightened its modding guidelines, and they explicitly ban bringing other companies' characters and worlds into mods, including content from other games. Around the same time, Take-Two got an unofficial Switch port of GTA 5, built on leaked source code, shut down, and back in 2023 it had a GTA 5 mod that let players chat with NPCs through AI taken down. Sony asked the creator of a fan-made multiplayer mod for The Last of Us Part II Remastered to pull it before release. Mojang had browser clones of Minecraft removed from GitHub, and SNK took down a fan recompilation of Metal Slug XX even though it contained no game files. On October 2, according to chasm, Activision filed a complaint against his tweet showing a decompiled MW2. Nintendo is a separate story: Mario has turned up in several mashups, and the company has a long history of going after fan projects with its characters.

The law is murky. Taking a program apart to make it work with another one is allowed in the EU and the US, but with conditions: you need a legitimate right to use your copy, and you can only dig into what's needed for compatibility and isn't available any other way. You also can't copy protected code, and in the EU the information you get can't be used to build a program with substantially similar code. In the EU, a license agreement can't forbid this, while in the US it can. Distributing other companies' characters, models and game files without the rights holder's permission is not allowed, which is why legitimate projects require players to own the games. That still doesn't make a mod legal by default: a publisher can demand that it be taken down.

Modders are split. Nexus Mods, the biggest modding site, doesn't ban AI, but since the summer it has required AI-made mods to carry special tags. Kotaku ran a column titled "Modders, Please Stop Putting Games Inside Other Games With AI." And the makers of the PC ports of Zelda and Banjo-Kazooie, who refuse to use AI on principle, called this week's AI-made Banjo-Tooie recompilation a "slopcomp" that nobody will be able to maintain.

Every project whose implementation could be checked works differently: none of them fuses the code of two games into one program. What it did show is that building a mod has become much faster: a prototype can appear in an evening or two, but only people can still turn it into something worth playing.

Mario mashups will probably be the first to get hit, given Nintendo's history. But shipping no game files isn't a guarantee either, as the Metal Slug XX case showed.

And Steve, who just took off over Leyndell, is clearly in no hurry to go home: Minecraft has turned out to be the easiest guest for any game.

New mashups pop up every day, and the questions about them are always the same.

The videos show a working mod, and Tobyn Jacobs also posted a phone recording of himself playing it on a laptop. But no code or download has been released, and he hasn't explained how it works.

No. The author hasn't released it. There is an independent open-source take on the idea for Mac, but any page offering an "official download" of the mod has nothing to do with him and isn't worth the risk.

Mario in Elden Ring, Minecraft in Skyrim (SkyCraft), skateboarding and Minecraft in Call of Duty: Modern Warfare 2, and the skateboarding mods for GTA: Vice City and Bully. Minecraft in GTA 5 and Spider-Man in Batman: Arkham Knight can be built from source. Almost all of them are rough and need your own copies of the games.

No. All of them are PC-only, and some, like SkyCraft, are Windows-only.

Most often Claude Opus 5.5 through Claude Code: its name is in the commit histories of SkyCraft, the MW2 skate mod and ArkWeb. OpenAI's Codex shows up too, along with a model called Astra (most likely OpenAI's GPT-6 Astra) and DeepSeek. Some of the big mashups, like Mario in Elden Ring, were made without any stated AI involvement.

It depends on the mod. You always need your own copy of the host game: Elden Ring, Skyrim, MW2 or Bully. The guest isn't always required: SkyCraft and Minecraft in GTA 5 run a real copy of Minecraft alongside, while the MW2 mashup downloads Minecraft's files from Mojang's servers and only needs Skate 3 for skate mode. Super Mario 64 and Skate 3 files have to come from your own copies of those old console games.

Taking a game apart to make it work with another program is allowed only under conditions: a legitimate right to use your copy, only the information needed for compatibility that isn't available any other way, and no copying of protected code. Distributing other companies' characters and game files without the rights holder's permission is not allowed. Publishers can demand that a mod be taken down, and Rockstar's guidelines already ban putting other games into mods.

You can't swap in money or progress by modifying a game or app on your own device: those are stored on servers, and mods only change what runs locally. But AI does help attackers look for holes in the services themselves and trick people, so caution still applies. Universal Modder also forbids touching online games with anti-cheat.