Troubleshooting and removal

No LogOutput.log anywhere means BepInEx never started, which means Windows never loaded the proxy DLL. In order of likelihood:

• winhttp.dll is not beside Nazi Zombies.exe. This is the cause most of the time. Open the game root and confirm it is right there in the same folder — not one level up, not in a subfolder.
• The archive extracted into a nested folder. If the game root contains a folder named after the ZIP, open it, move its six items up one level, and delete the empty folder.
• You are looking at the wrong game folder. Use Steam → right-click the game → Manage → Browse local files to be certain.
• Antivirus removed it. Check the quarantine list. A proxy DLL beside a game executable is the exact shape some products flag on sight. Restore it and exclude the game folder.

First, confirm it is actually the mod: rename winhttp.dll to winhttp.dll.off and launch. If the game runs, BepInEx is involved; if it still crashes, the problem is the game itself and BepInEx is a bystander.

If it is BepInEx, the usual causes are a partial extraction (a missing dotnet folder is the classic one, and it is by far the largest part of the archive), or a 32-bit BepInEx build in a 64-bit game. This package is win-x64, which is correct for this game — but if you previously installed a different build, remove it completely before extracting this one.

Clean re-extraction fixes this nearly every time. Delete BepInEx, dotnet, winhttp.dll, doorstop_config.ini and .doorstop_version, then extract the archive again in one go.

The interop layer is the generated managed mirror of the game, and nothing works without it. An empty or missing folder means the first launch did not complete.

The fix is almost always simply to let it finish. Delete the interop and cache folders if they exist, launch the game, and this time wait — a black window or a frozen splash for anywhere up to a few minutes is normal on this launch, and it is not a hang. Do not close it until you reach the main menu.

If it genuinely fails rather than being interrupted, check that BepInEx\unity-libs\2022.3.62.zip is present and around 3.5 MB. That file is the pre-seeded base library cache this package exists to provide; without it, BepInEx tries to download one and can fail offline or behind a firewall.

A half-written interop folder produces strange, inconsistent symptoms — a mod that loads but does nothing, missing types in the log, or a crash partway through startup.

It is a clean fix. Close the game, delete both of these folders, then launch and let it run to the main menu without interruption:

• BepInEx\interop
• BepInEx\cache

Both are regenerated automatically. Nothing you configured is lost — your settings live in BepInEx\config, which you should leave alone.

If the log reaches Chainloader started but never mentions the mod in question, BepInEx is healthy and simply is not finding that plugin. Check in this order:

• Is the DLL directly in BepInEx\plugins? A subfolder such as plugins\UngodlyMysteryBox\ will not be found.
• Is it the DLL and not the archive? A .rar sitting in plugins is ignored entirely. Extract the DLL out of it.
• Is the filename intact? Windows sometimes appends (1), or an archive tool produces .dll.dll. It must end in a single .dll.
• Is the file the right size? 172 KB for the zombie AI, 23.5 KB for the mystery box. A file of a few hundred bytes is a failed download — check the SHA-256 on the downloads page.
• Did antivirus take it? Same story as the loader. Check quarantine.

If the load line is in the log, the mod is running and this is an input problem rather than an install problem.

• Something else owns the key. Overlays bind function keys aggressively — Steam, Discord, GeForce Experience, OBS, Bandicam and MSI Afterburner are the usual suspects. Close them one at a time, or rebind.
• Rebind it. Open BepInEx\config\UngodlyEmeraldZombieAI.cfg, find GuiToggleKey in the [GUI] section, set it to a free key, and restart. It can also be rebound live from the panel once it is open.
• Try it at the main menu. The screenshots on this site were taken there, and it rules out anything in-match capturing input.
• Check the config file exists at all. If UngodlyEmeraldZombieAI.cfg is missing, the mod never actually initialised, and the real problem is above.

Check these in the panel, in this order:

• ModEnabled in [General] — if this is off, the mod loads but deliberately does nothing.
• ReplaceStockAI — off means the mod watches and fires its events without changing behaviour, which is a real mode intended for modders.
• EnableInOffline / EnableInOnline — one of these governs the session you are in.
• OnlyDriveAsHost — in online co-op only the host drives the brains. If you are a client, you are seeing the host’s AI through normal sync, which is correct and intended.
• The header readout — if it says the mod has stood down after repeated internal errors, restart the level or the game to re-arm it, and check ErrorLog.log for what tripped it.

Also worth knowing: DriveSpecials is off by default, so special and boss zombies keep the stock AI on purpose. If you are watching a boss round, that is expected.

Because the box has no interface, the console is the only way to tell. Check the log for All 3 patch groups engaged.

• If that line is absent, the DLL is not loading — work through the plugin checks.
• If one group reports [SKIP], a game update renamed a target. That path runs vanilla while the others keep working. Check whether a newer version of the mod exists.
• If you see it standing down for the session, the kill switch tripped after repeated faults and the box is deliberately back to 100% vanilla. Restart the game to re-arm it, and check ErrorLog.log for what caused it.
• If the line is there and it still feels the same, buy a few more times. The change is statistical, not visual — there is no new animation or sound. Set logging to Debug in BepInEx.cfg and you will see a per-roll verdict naming the tier and the pity state.

Possible by design, and rarer than vanilla. The mod defers any weapon you already hold, or received in your last three grants, behind every fresh option left in the current bag cycle — but a bag’s final card can still be one you hold.

Duplicates are kept reachable on purpose: the game’s own weapon-grant call on a weapon you already have is its ammo refill path, so removing them entirely would remove a real use of the box. Across the author’s 400,000-roll validation there were zero back-to-back identical grants. The full model.

Yes, freely, in either direction. The rolled box index was never synchronised over the network by the game — only the buyer’s own client ever reads it — and this mod keeps that contract exactly. No RPCs are added and no Photon messages are altered.

Each player simply gets their own client’s odds: yours are Ungodly, theirs are vanilla. Host or client makes no difference. Why this works.

Expected on the heaviest waves, and directly tunable. Turn on ShowOverlay and OverlayShowsPerf in [GUI] so you can see the budget pools rather than guessing, then work through the cheaper horde recipe.

The two settings with the largest effect are MaxBrainThinksPerFrame and FarThinkRate. If the think budget is pegged at its ceiling every frame, raising FarThinkRate — so fewer distant zombies ask for a think at all — helps more than lowering the budget does.

That is the documented engine boundary rather than a bug. Direct player-body effects can only be applied by the machine that owns that player, so online they apply to the host’s own character (and to any client also running the mod, for their own body).

Damage itself is completely unaffected — it goes through the game’s own networked damage path like any stock hit, so the horde remains a genuine threat to everyone. The full co-op model explains why.

Game updates can move things under a mod. Two outcomes are normal:

• BepInEx rebuilds interop automatically. The first launch after an update is slow again, for the same reason the very first one was. Let it finish.
• The mod stands down. If a patch renames or removes something it needs, it reports it and returns the zombies to the stock AI for the level rather than degrading your run. Check ErrorLog.log, and check whether a newer version of the mod has been released.

If the update was large, delete BepInEx\interop and BepInEx\cache and let them regenerate cleanly.