MW2 x Risk of Rain 2

MW2 (2009) inside Risk of Rain 2. You play the MW2 Soldier, a new survivor built from your own MW2 install: its guns, movement, viewmodel, sounds, HUD and menus. Risk of Rain 2 still runs the damage, items and enemies, so your RoR2 items work off MW2 guns.

Tuned for RoR2's big stages and endless waves: faster movement, unlimited sprint, RoR2-style ammo, scaled damage and longer killstreaks. Each is a setting.

https://github.com/user-attachments/assets/95c1cf51-5248-4b14-bf3f-a19d3c2d4766

2-minute showcase, sound on (MP4 download, 9.5 MB).

Get it: MW2xRoR2 on Thunderstore for any Risk of Rain 2 mod manager, or the manual zip from Releases. Steps are under Install.

MW2's minimap, rank, perks, killstreaks and ammo alongside RoR2's health, skills and objective.

What's in it

• MW2's guns with their attachments and camos, including akimbo, underbarrels, the riot shield and the knife lunge
• Create-a-Class through MW2's own menus. Perks and Pro perks show up as RoR2 items, and deathstreaks, Last Stand and One Man Army all work
• All 15 killstreaks: UAV on the minimap, Care Packages, the Predator, AC-130 and Chopper Gunner rides, Harriers, Pave Low, Stealth Bomber, EMP and the Nuke. Earned from kill streaks, or found as items in chests. Monsters can shoot your aircraft down
• MW2's full XP and rank system with its challenges and unlocks, saved across runs
• MW2's HUD and minimap, first person or third person, and your RoR2 items show on the soldier
• MW2's soldiers with every faction skin, MW2's death animation and death camera, and MW2's effects, sounds and announcer
• MW2's match start on the first stage: Choose Class, the countdown and the spawn music
• Co-op through normal RoR2 lobbies. Teammates see your soldier, your streaks and your aircraft

What you need

• Risk of Rain 2 and Call of Duty: Modern Warfare 2 (2009), both on Steam (PC), with MW2's multiplayer content installed. No game files come with the mod: it reads your own MW2 install.
• Windows 10 or 11, 64-bit. No extra runtimes.
• Tested on RoR2 Steam build 25475991 (the October 8, 2026 update) and MW2 Multiplayer Steam build 25374019.
• In co-op, everyone needs the same version of the mod and RoR2BepInExPack (mod managers install it, the manual zip includes it). The lobby tells you if anything doesn't match.

Status

• Solo is tested on Risk of Rain 2's October 8, 2026 update.
• 2-player co-op has been played on v0.4.5. Mixing a mod-manager install with a manual install hasn't been re-tested since the v0.4.4 desync fix.
• 3-4 player lobbies and other mods aren't tested yet (with other mods, include your mod list in reports).
• Windows only.
• Balance is still being tuned. Stuck on geometry? F6 gets you out, and the spot is saved to BepInEx\mw2_stuck.log so you can send it in.

Install

MW2xRoR2 is on Thunderstore, so any Risk of Rain 2 mod manager can install it and keep it updated. Or install it by hand with the manual zip. The mod finds MW2 in your Steam libraries by itself. Pick the MW2 Soldier on character select.

r2modman or Thunderstore Mod Manager

1. Open the mod manager, pick Risk of Rain 2 and a profile (a new one is fine).
2. Go to Online, search for MW2xRoR2 and click Download. Its dependencies come with it.
3. Click Start modded.

Or click Install with App on the Thunderstore page.

Gale

Install mods, search for MW2xRoR2, Install, then Launch modded.

Manual (no mod manager)

1. Find your Risk of Rain 2 folder: in Steam, right-click Risk of Rain 2 > Manage > Browse local files.
2. Download BepInExPack with Manual Download. From its zip, extract what's inside the BepInExPack folder into your Risk of Rain 2 folder, so winhttp.dll sits next to Risk of Rain 2.exe.
3. Download MW2xRoR2-v<version>-manual.zip from Releases and extract it into the same folder. The mod ends up in BepInEx\plugins\MW2xRoR2, with RoR2BepInExPack beside it in BepInEx\plugins\RoR2BepInExPack. Mod managers install that one too, and co-op needs everyone to have it.
4. Start Risk of Rain 2 from Steam as usual.

To play without mods, rename winhttp.dll in the game folder (for example to winhttp.dll.off), and rename it back to play with them.

Updating

• Mod manager: update MW2xRoR2 from the manager's installed mods. Your settings and rank stay in the profile.
• Manual: extract the new manual zip over the old one.

Controls

Action	Key
Fire / aim down sights	RoR2's primary / secondary skill keys (left / right mouse by default)
Reload	R
Sprint (holds your breath while aiming)	your MW2 key (or RoR2's sprint key)
Crouch / prone	your MW2 keys (Left Ctrl / Z)
Primary / secondary weapon	1 / 2 (your MW2 weapon-switch key works too)
Lethal (hold to cook) / tactical	your MW2 keys (G / F)
Knife	your MW2 key (V)
Underbarrel attachment	your MW2 key (3)
Use killstreak	your MW2 key (5)
Tactical Insertion	X (also RoR2's special-skill key, unless that's R)
Create-a-Class / Create-a-Streak (character select)	F3 / F5
Change class (see below)	F4
First / third person	F7
MW2 mode off / on (to get unstuck)	F6

"Your MW2 key" means the mod reads your MW2 config (MW2's or IW4x's) and uses your own binds, so they work like they did in MW2. The key in brackets is only for players without an MW2 config.

Loadout and settings

In the game. On character select, the MW2 Soldier's Loadout tab has:

• Skin: MW2's faction soldiers.
• Class: your Create-a-Class classes and MW2's default classes. Create-a-Class (F3) is MW2's own menu: weapons, attachments, camos, perks, equipment and deathstreak.
• Killstreaks: your three streaks. Click to open Create-a-Streak (F5).
• Rank: your MW2 rank, plus Unlock everything. That switches to a separate profile with every weapon, attachment, camo, perk and killstreak; your own progress is kept apart.

In a run, F4 opens Choose Class, with MW2's rule: right after you spawn the new class is yours on the spot, but once you've fought it comes with your next spawn (the next stage, a revive or a Tactical Insertion). One Man Army, the MW2 Soldier's utility skill, is the mid-fight change. F7 switches first / third person (you spawn in third person). RoR2's Settings > Gameplay has MW2 First-Person FOV (65-90) and MW2 Third Person Only.

In the config file. Everything else is in com.buhhrad.mw2ror2.cfg. Open it from your mod manager's config editor, or in BepInEx\config\, and edit it with the game closed. Every setting is explained in the file; these are the ones you're most likely to want:

Setting	Default	What it does
[Keys], [Equipment], [MW2], [Killstreaks] key settings	see Controls	Rebind the mod's keys (F7 is fixed). Keys from your MW2 config win; set [Keys] UseMw2Binds to false to use these instead
[Ammo] RoR2Ammo	true	Guns never run out of reserve; launchers, grenades and tacticals recharge on cooldowns. Off: [MW2] AmmoMode (Scavenger, Infinite or Stock)
[Killstreaks] KillScale	4	Kills a streak needs, times MW2's (RoR2 sends far more enemies). 1 = MW2's
[Killstreaks] ChestChance	0.05	Chance a chest drops a killstreak instead of its item
[Killstreaks] Faction	US	Announcer voice: US, UK, NS, PG, RU or AB
[Balance] DamageMultiplier	1.25	Damage of every MW2 round (snipers, explosives and equipment have their own scales on top)
[Balance] DamageTakenScale	1	Damage you take from enemies
[Balance] MoveSpeedBoost	1.45	How much faster than MW2's own speed you move (RoR2's maps are big)
[Balance] UnlimitedSprint	true	Sprint never runs out
[Balance] RegenDelay	0	MW2 health regen after this many seconds unhurt. 0 = off, RoR2's healing only (MW2's was 5)
[Progress] KillXpScale	0.1	XP per kill as a share of MW2's 100
[MW2] Prematch	true	MW2's match start on the first stage: Choose Class, countdown, no drop pod
[MW2] WeaponVolume	0.35	Volume of MW2's gun sounds
[View] ThirdPersonStart	true	Spawn in third person
[General] SkipIntro	true	Skip RoR2's opening cutscene
[General] FlinchScale	0.35

Something wrong?

• No MW2 Soldier on character select: the game started without mods. With a mod manager, launch with Start modded (r2modman, Thunderstore Mod Manager) or Launch modded (Gale), not from Steam. If it still happens, fully exit Steam (Steam menu > Exit), start it again and launch again.
• Stuck in the level: press F6 to turn MW2 mode off, walk out with RoR2's movement, then press F6 again to turn it back on.
• "MW2 setup mismatch" in the lobby chat: someone's game numbers RoR2's content differently, so the run would desync. Usually a manual install from before v0.4.4, without RoR2BepInExPack: extract the current manual zip over it.
• "MW2 not found" or "No MW2 weapons loaded" in the log: the mod looks through all your Steam libraries for MW2 and didn't find it. Check that MW2's multiplayer is installed, or set CommonMpPath in com.buhhrad.mw2ror2.cfg to your MW2 folder's zone\<language>\common_mp.ff.
• Anything else: close the game and attach BepInEx\LogOutput.log to an issue. With a mod manager it's in the profile's folder (the manager's settings can open it).

What it does on your PC

• Reads your MW2 install's files. Nothing is copied out of them or changed.
• Writes only inside the BepInEx folder: its settings (config\com.buhhrad.mw2ror2.cfg), your MW2 progress (config\mw2-ror2\) and its logs.
• If you get stuck in a level, it notes the spot in mw2_stuck.log and saves a screenshot of it to mw2_stuck\ (at most 12 per session), so stuck spots can be reported and fixed.
• If the game freezes for 15 seconds, it writes a hang report (a copy of the log and a memory dump of the game) to hangs\.
• It makes no internet connections of its own. In co-op it talks to the other players through RoR2's own multiplayer.

None of it leaves your PC unless you attach it to an issue yourself.

Build from source

You can read every line of the mod here, and build it yourself.

1. Install Rust (stable) and the .NET SDK.
2. Put BepInExPack (RoR2's, with BepInEx\core) in deps\bepinexpack. It isn't in the repo.
3. cargo build --release -p mw2sim builds mw2sim.dll. Cargo fetches the IW4L crates from chasmlol/2010-rust-rewrite-mashup at a pinned commit.
4. dotnet build plugin\MW2RoR2.csproj -c Release builds MW2RoR2.dll against your own Risk of Rain 2 install (pass -p:RoR2Managed=<path>\Risk of Rain 2_Data\Managed if it isn't in the default Steam folder).
5. Copy target\release\mw2sim.dll and plugin\bin\Release\netstandard2.1\MW2RoR2.dll over the ones in your install's plugin folder.

Made with AI

buhhrad designed this mod, directed the work and playtested it. The code was written with an AI coding agent (Anthropic's Claude, through Claude Code).

Credits

• IW4L by vladtrc, an open-source MW2 (2009) runtime written in Rust, through chasmlol's 2010 Rust Rewrite Mashup fork. The mod's movement, weapon, animation and data code is built on their crates (Apache-2.0).
• RoR2BepInExPack by Risk of Thunder (MIT), included in the manual zip.
• BepInEx, HarmonyX and the other libraries listed in tools/installer/licenses/THIRD-PARTY.txt.

License

Source-available, not open source: read it, check it, play it, build it for yourself. Don't reupload or redistribute it anywhere. See LICENSE.md. Third-party parts keep their own licenses.

Not affiliated with or endorsed by Activision, Infinity Ward, Hopoo Games or Gearbox.