Halo 3 Invincible Allies
🟡 Updated this yearPreview

🔍 Analysis
- 👍 1.4% endorsement rate — high engagement, a strong quality signal
- 🏆 #77 of 585 Campaign mods in this game by downloads
📋 About This Mod
Makes all friendly AI in the campaign invincible.
All of your friendlies throughout the campaign will now become invincible by all means. This mod includes the marines, ODSTs, workers, and Elites. Allies should also be immune to flood infections thanks to state of the art anti-bungus vaccines.
If there are any bugs or issues please do let me know.
Some Marines Are Scripted to Die and this is not changed by this mod!
Those Scripted to Die:
A couple marines at the beginning of "Floodgate"
The 2 marines by the crashed longsword in "The Ark"
Miranda Keyes in the mission "The Covenant"
Johnson in the mission "Halo"
How to install
-Backup your original map files (just in case)
-Extract my file using 7zip
-Simply copy-paste these files to where yours are (mine would be: R:\SteamLibrary\steamapps\common\Halo The Master Chief Collection\halo3\maps)
-Run MCC with easy-anti-cheat disabled
Thats it! Just replace your map files with mine, manually is always safer. Then run with anti-disabled and load into a mission!
Known Issues
Sometimes allies are set to be killed right as the player arrives; however, my mod prevents it, and on some occasions, this will cause the allies to stand still and not track/follow the player. The most common occurrence of this is on the mission The Ark in which 3 marines that are holding an area outside the Forward Unto Dawn landing zone tend not to auto-follow. I am unsure of how to fix this at the moment.
My Other Versions:
-Halo Reach: here
-Halo CE: here
-Halo 2: here
-Halo 3 ODST: here
-Halo 4: here
Troubleshooting
Step 1: Check your MCC version
-If a MCC update was released after the most recent mod version then wait a bit and I'll update the mod to the latest version
Step 2: Load up a different mission
-Due to the way the MCC stores saves, clicking resume or loading up the same mission may cause crashing or the changes to not apply
Step 3: Validate your files then redownload the mod
-You can do this by: right-click on the MCC, choose properties, then local files, and then click "validate local files" this will scan for any corrupt or changed files and restore them to their default setting
Step 4: Uninstall and Reinstall the MCC
-If it comes down to it, simply try reinstalling the entire game to make sure everything is back to square 1 safely
Step 5: Abandon Hope all Ye Who Enter Here
-Post in the bugs section or comments, and I'll get to you as soon as I see!
📊 Mod Details
- Game
- Halothemasterchiefcollection Mods
- Author
- krazykombat14
- Version
- 3.1.1
- Downloads
- 946
- Endorsements
- 13
- Category
- Campaign
- Created
- 1/29/2023
- Updated
- 12/1/2025
🔧 How to Install Halo: The Master Chief Co Mods
Download from Nexus Mods.
📖 Full step-by-step install guide for Halo: The Master Chief Co →
Visit the official mod page for specific installation instructions for this mod.
🎮 Need cheat codes or console commands? Check ur gaming wiki for Halo: The Master Chief Co commands, item IDs, and more.
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