How to install and play WaW Halo 3 Zombies (Halo 3 in World at War's Nacht der Untoten)

Build the mod from your own World at War and Halo MCC installs: the Mod Tools, Python, Install.bat and Play.bat, plus controls, Pack-a-Punch, fixes and uninstall.

WaW Halo 3 Zombies turns Nacht der Untoten into Halo 3: you play Master Chief against Flood combat forms, with Halo 3 guns, grenades, sounds and HUD, dual wielding and a Pack-a-Punch machine. This guide follows v1.1.0 from Mr-Joshh/World-at-War-Zombies-Halo-3-Mod. New to mods? Read Start here first.

The download has no game files. Its installer reads your own copies of both games and converts the models, textures, sounds and animations on your PC. You must own both.

1. What you need

Call of Duty: World at War, the Steam version. The scripts are matched to it.
World at War Mod Tools 1.0 plus the 1.1 to 1.4 updates, installed into a World at War folder (your Steam folder or a copy). Activision no longer hosts them; the README points to community copies (archive.org item cod-waw-modtools for 1.0, the updates via wiki.modme.co). The installer checks for bin\linker_pc.exe, bin\converter.exe, raw\, model_export\, xanim_export\ and main\.
Halo: The Master Chief Collection on Steam, with Halo 3, Halo 3: ODST, Halo: Reach and Halo 2: Anniversary installed, multiplayer maps included. MCC is only read, never changed or launched.
Python 3.9 or newer from python.org, with Add python.exe to PATH ticked.
Internet once, to download about 300 MB of open-source tools.
Disk: about 1.6 GB in the mod folder’s work\ while building (you can delete it after), and about 0.5 GB added to the Mod Tools folder.
Windows. Tested on Windows 11 with the Steam versions of both games.

2. Install

Download WaW-Halo-1.1.0.zip from the Releases page and extract it somewhere. A path without special characters is safest. To update from 1.0.0, extract over the old folder or into a new one.
Run Install.bat. It finds World at War and MCC through Steam and asks for any folder it can’t find, like the Mod Tools if they’re in a copy of the game.
Wait. It sets up a private Python environment, downloads the .NET 9 SDK, Reclaimer and vgmstream into work\tools (nothing system-wide), reads the Halo assets from MCC, builds mod.ff and halo3.iwd, and installs them to %LOCALAPPDATA%\Activision\CoDWaW\mods\halo3. It takes about 15 minutes.

If a step fails, fix what the message says and run Install.bat --from <step number> to carry on from there. Install.bat --reconfigure asks for the game folders again.

3. First launch

Make sure Steam is running.
Run Play.bat. It starts World at War on Nacht der Untoten with the mod, and binds key 3 in your WaW profile.

Nacht der Untoten only. Don’t load the mod on other maps. It was made and tested solo; co-op hasn’t been tested.

4. Controls

Key	Does
Left mouse	Fire (the left gun when dual wielding)
Right mouse	Zoom on the Sniper Rifle, Carbine and Beam Rifle. Fires the right gun when dual wielding
F (hold)	Buy wall guns, ammo, doors, the box, Pack-a-Punch. Take weapons and pick up guns
H	Dual wield (take a one-handed gun into the left hand)
B	Drop the left-hand gun
R	Reload
G / middle mouse	Throw the selected grenade
3	Cycle grenade type (frag, plasma, spike, incendiary)
V	Melee
Hold the trigger	Charge the Spartan Laser. Overcharge the Plasma Pistol (2 s)

You can dual wield the Magnum, SMG, Plasma Pistol, Plasma Rifle, Spiker and Mauler, in any pair.

5. Prices and Pack-a-Punch

Wall guns cost what the WWII gun on that wall cost in stock Nacht. Ammo costs half.
You start with the M6G Magnum. Every other gun can come out of the mystery box (950).
Pack-a-Punch is upstairs in the large room and costs 5000. It turns each gun into its Halo: Reach, ODST or Halo 2 version.
Doors and debris cost 1000 each.
The Flood can drop an Overshield (red, 200 extra health that doesn’t regenerate) and Active Camouflage (blue, 30 seconds where the Flood can’t see or attack you).
You carry at most 2 of each grenade type, refilled each round. They can’t be cooked.

6. Known problems / fixes

The installer fails on the first run: this sometimes happens. Run it again.
“Cannot rebuild maps/… - no matching original”: your World at War files are a different version from the Steam release the patches were made for.
The linker reports EXE_ERR_HUNK_ALLOC_FAILED: close other programs and run Install.bat --from 25.
MCC files missing: install the Halo 2: Anniversary, Halo 3, ODST and Reach content in Steam, multiplayer maps included, and run Install.bat again.
The game asks to run in safe mode after a crash: answer No.
Linker log: <Mod Tools>\mods\halo3\linker.log.
Known limits: switching camo on or off replays the held gun’s raise animation, and the Ray Gun stays visible during camo.

Don’t share the work\ folder or the built mod.ff and halo3.iwd. They contain converted game assets and are for your personal use.

7. Uninstall

Run Uninstall.bat. It removes the installed mod, asks before deleting the files the build added to the Mod Tools folder, and restores your zone_source\mod.csv. Then delete the mod’s folder. Nothing in the Steam installs of either game is changed.