Mods That Add Multiplayer to Single-Player Games

27 January 2026

Gaming solo has its charm—no doubt. You get to explore vast open worlds, make choices without judgment, and totally immerse yourself. But let’s be honest: playing with friends? That just multiplies the fun tenfold.
Yet, not all games are built with multiplayer in mind. Some of the best single-player titles out there are just begging for a “bro, pass the controller” kind of moment. Thankfully, the modding community has swooped in like the heroes they are, cooking up some incredible multiplayer mods that bring fresh life to our favorite solo adventures.

If you’re itching to bring your buddies along for your next big quest or just want to mess around with friends in a traditionally lonely game world, you’re in the right place.

So buckle up—we’re diving headfirst into the best mods that add multiplayer to single-player games. This is gonna get juicy.

Why Add Multiplayer to a Single-Player Game?

Let’s start with the big “Why?”

Why mess with something that’s already great on its own?

Simple answer: because fun is better shared. Picture this—you’re surviving the zombie apocalypse in a gritty solo survival game. Now imagine doing it with your best friend, shouting tactics (or panicking together) over Discord. That’s the kind of chaotic joy these mods unlock.

Plus, many single-player games have huge, detailed worlds and complex systems. Adding multiplayer breathes new life into those systems and gives players reasons to return. It’s like watching your favorite movie again… but this time, with director’s commentary and a friend throwing popcorn at your head.

1. Skyrim Together Reborn — The Coop Elder Scrolls Adventure We Never Knew We Needed

Platform: PC
Game: Skyrim Special Edition

Let’s be real: Skyrim is practically a religion at this point. But one thing it always lacked? Seamless multiplayer support. Enter Skyrim Together Reborn, a fan-made multiplayer mod that lets you and up to 8 friends explore Tamriel together.

You can:
- Slay dragons side by side.
- Loot dungeons as a squad.
- Even hold impromptu town brawls if things get too peaceful.

Sure, there might be the occasional hiccup (like when your friend gets launched into the sky by a bugged troll), but that’s all part of the charm. What was once a solitary, immersive RPG becomes a wild fantasy sandbox of shared chaos and glory.

2. Stardew Valley Multiplayer Mod (Before It Was Official)

Platform: PC
Game: Stardew Valley

Fun fact: Before Stardew Valley added official multiplayer, modders made it possible. The early Stardew Valley Multiplayer Mod was the reason you could co-run a farm with your bestie before it was cool (and before it was patched into the base game).

Even today, mods like Stardew Valley Expanded and content-heavy co-op mods still enhance that multiplayer experience, letting you:
- Build massive farms together.
- Go spelunking in the mines with backup.
- Host community events like real-life festivals.

Farming’s never been so fun—or adorable.

3. Fallout: New Vegas Coop Mod — Wasteland With Company

Platform: PC
Game: Fallout: New Vegas

Fallout: New Vegas is a cult classic, but walking the Mojave Wasteland alone can be... lonely. That’s where the Co-Op mod steps in. Still in development and mostly experimental, this mod lets you and a friend roam the wasteland together.

Expect:
- Shared dialogue choices (oh yes, you can argue over who gets to be the sarcastic one).
- Cooperative looting and combat.
- Mutant slaying duos and (eventually) dynamic quest syncing.

It’s not perfect yet, but modders are constantly tweaking it. It’s like Fallout meets buddy comedy—and we’re here for it.

4. Just Cause 2/3 Multiplayer Mods — The Definition of Peak Chaos

Platform: PC
Game: Just Cause 2 and 3

If Just Cause is known for one thing, it’s blowing stuff up in ridiculous ways. So naturally, someone thought, “Why not add 100 players and see what happens?”

Enter the Just Cause 2 Multiplayer Mod and its spiritual successor for JC3.

What you can do:
- Race planes through cities.
- Grapple onto your friend’s jet and ride shotgun.
- Turn the entire island into a high-explosive playground.

No objectives, no rules. It’s basically Grand Theft Auto’s chaotic cousin on steroids. And honestly? It’s a freaking blast.

5. The Forest — Survive Together, Scream Together

Platform: PC
Game: The Forest

Okay, yes—The Forest has multiplayer built in these days. But historically, it was solo-only. Mods helped pave the way for that multiplayer experience.

Even now, mods improve the base multiplayer:
- Bigger lobbies.
- Shared inventory systems.
- Enhanced survival mechanics for co-op fun.

Ever wanted to build a treehouse with your friend while being attacked by cannibals in the middle of the night? Welcome to The Forest multiplayer experience. Bring snacks. And maybe a nightlight.

6. Resident Evil 5/6 Split-Screen Mod — Local Coop, Old School Style

Platform: PC
Game: Resident Evil 5 & 6

Capcom made some... questionable choices with their PC ports. Specifically, removing local co-op from games originally built around it. But guess who fixed that? Yup, modders.

The Split-Screen Co-op Mod for Resident Evil 5/6 brings back couch co-op.

You can:
- Blast zombies side by side.
- Argue over who hoards all the grenades.
- Relive the classic RE experience with a friend, the way it was intended.

Sometimes, nothing beats couch co-op vibes. Pass the chips.

7. GTA V FiveM & RAGE MP — Multiplayer, Modded, and Massive

Platform: PC
Game: Grand Theft Auto V

Now yes, GTA Online is Rockstar's thing. But FiveM and RAGE Multiplayer crack that wide open.

These platforms let players run their own servers—with their own rules.

Think:
- Roleplay servers where you’re a cop, criminal, or pizza delivery guy.
- Battle royale mods.
- Racing tournaments and zombie survival.

It turns GTA V into a full-on multiplayer mod universe. From serious RP to chaotic mayhem, you’ll never run out of stuff to do.

8. Half-Life 2: Synergy — Coop Gordon Freeman (Kinda)

Platform: PC
Game: Half-Life 2

Ask any Valve fan and they’ll tell you—Half-Life 2 is holy ground. So playing it in multiplayer is like rewriting the Bible with your friends.

Synergy is a mod that adds co-op to the entirety of Half-Life 2 and some of its episodes. It’s surreal, in the best way, watching multiple Gordons running around.

Expect:
- Enemies scaled for multiple players.
- Collaborative puzzle-solving (or chaotic miscommunication).
- That moment when someone accidentally tosses a grenade during a stealth section.

Classic Valve jank, now with friends.

9. Dark Souls: Seamless Co-op — Git Gud With Your Homies

Platform: PC
Game: Dark Souls III & Elden Ring (via separate projects)

Dark Souls multiplayer is notoriously clunky—limited summoning systems, constant invasions, and more rules than a D&D campaign.

Mods like Seamless Co-op (for Elden Ring and DS) strip all that nonsense away. You and your buddy can:
- Join one another persistently.
- Share quest progression.
- Explore the entire world together, no disconnects.

It’s like a Soulsborne MMO-lite, and it makes the brutal experience less about dying alone in shame and more about screaming with your pal in glorious agony.

10. Minecraft Mods — Infinite Multiplayer Possibilities

Platform: PC
Game: Minecraft

Minecraft already has multiplayer, sure. But the modding scene? It’s next level. With mods like:
- Forge and Fabric for installing hundreds of tweaks.
- Pixelmon for a full Pokémon MMO inside Minecraft.
- RLCraft for survival multiplayer that actually punishes you for breathing wrong.

You’re not just playing together. You’re creating entire worlds—and then blowing them up with TNT for laughs.

Honorable Mentions You Shouldn’t Sleep On

- Portal 2: Community co-op maps – Brain-busting puzzle action with a friend.
- Terraria tModLoader – Wild multiplayer mods from RPG elements to new bosses.
- Morrowind Multi-Player (TES3MP) – Tamriel in its early 2000s glory, now with friends.
- The Legend of Zelda: Breath of the Wild (Yuzu + Mods) – Experimental but promising!

Wrapping It Up — Modding Is the Ultimate Cheat Code

Here's the thing: Developers might not always include multiplayer. But that doesn’t mean you have to go it alone. With a little modding magic, you can bring entire squads into worlds that were once built for just one.

Sure, there might be bugs. Glitches. Sync issues. But that’s part of the journey. The chaos makes it fun. Just imagine Skyrim’s main quest while your friend accidentally sets Whiterun on fire. Priceless.

So if you’ve ever wished your favorite single-player game could handle more than just you—now you know it can. Game on, squad up, and mod everything.