This is a simple mod that makes allied NPCs in the Halo 2 campaign invincible. Nothing else has been changed.
Check the Related Mods section for mods that do the same thing in other Halo games.

NOTE: This mod may have some issues in co-op (anti-cheat must be disabled to play the map in co-op). Levels will load and play as normal until the map freezes and the game session is closed, booting both players to the main menu. Currently the level Gravemind is known to do this, but others may have this same issue. Why this issue occurs is unknown, as the maps have only a single tag per NPC .hlmt file modified, but it may be an issue with memory of some sort.

Installation
It is highly recommended that you backup the original 13 map files that are being replaced by this mod:

• 01b_spacestation.map (Cairo Station)
• 03a_oldmombasa.map (Outskirts)
• 03b_newmombasa.map (Metropolis)
• 04a_gasgiant.map (The Arbiter)
• 04b_floodlab.map (The Oracle)
• 05a_deltaapproach.map (Delta Halo)
• 05b_deltatowers.map (Regret)
• 06a_sentinelwalls.map (Sacred Icon)
• 06b_floodzone.map (Quarantine Zone)
• 07a_highcharity.map (Gravemind)
• 07b_forerunnership.map (High Charity)
• 08a_deltacliffs.map (Uprising)
• 08b_deltacontrol.map (Great Journey)
  

Installation Steps
"Normal" Install

• Navigate to your Halo 2 MCC installation's map folder (for Steam version, default is C:/Program Files (x86)/Steam/steamapps/common/Halo The Master Chief Collection/halo2/h2_maps_win64_dx11).
• Extract the contents of the mod directly into the h2_maps_win61_dx11 folder and overwrite existing files (or place them in a backup folder if you wish to return to the vanilla maps in the future).
  

Assembly Patches
These instructions are for the Assembly Patches downloads of this mod. It requires you to have the Assembly modding tool. These instructions must be repeated for each map you want to patch.

• Rename the map file(s) you want to patch to something else so the original ones aren't overwritten (for example add "_old" to the name).
• Open Assembly and go to "Tools" > "Map Compressor". Select the map file you want to patch and select "De/Compress Map" to decompress it. NOTE: if you want to decompress multiple files at once, place them into a folder and then select that folder to decompress files in. If you select the "h2_maps_win64_dx11" folder, Assembly will attempt to decompress every file inside the folder.
• After decompressing the map file(s), go to "Tools" > "Map Patcher", then go to the "Apply Patch" section.
• Select the patch corresponding to the map you want to patch (e.g., the Cairo Station patch for the Cairo Station map) in the "Patch to Apply" field
• Select the vanilla version of the map you're patching in the "Unmodified Map" field
• Select where to save the output map in the "Output Map" field. Make sure it has the name of the original map file so the game picks it up.
• Click "Apply Patch" at the bottom of the window.
• Go back to "Map Compressor" and select the newly patched map file, then select "De/Compress Map" to compress it.
  
  

Uninstallation
Uninstalling the mod requires replacing the mod's map files with the vanilla versions from the latest MCC update. There are a couple of ways to do this:
Option 1:
Copy the vanilla map files from your backup folder into your Halo 2 MCC installation's map folder and overwrite existing files.
Option 2:
    1. Download "Original Halo 2 Map Files" from this mod page's Files section.
    2. Extract the map files into your Halo 2 MCC installation's map folder and overwrite existing files.
Option 3 (Steam Only):
    1. Delete the map files listed in the "Installation" section above from your Halo 2 MCC instllation's map folder.
    2. Open Steam and navigate to your game library.
    3. Right-click on Halo: The Master Chief Collection in your library and select "Properties" to open the "Properties" window.
    4. In the "Properties" window, navigate to the "Local Files" section and select "Verify integrity of game files...".
    5. Wait for Steam to re-download the vanilla map files for Halo 2 automatically.

Using the Mod
You must launch MCC with anti-cheat disabled in order for the maps to load correctly. Once the game has launched, just select and play the Halo 2 campaign as normal.

Compatibility
This mod is incompatible with any mods that replace the map files for Halo 2, as the changes made by the mod are a part of the map files themselves. Overwriting this mod's map files means that the changes are no longer present.

Allies Made Invincible by the Mod
Master Chief allies:

• Marines
  

Arbiter allies:

• Elites
• Grunts
• Jackals (only in Sacred Icon)
• Hunters
  

Related Mods
krazykombat14's Invincible Allies mods (for other MCC titles):

• Halo Reach Invincible Allies
• Halo CEA Invincible Allies
• Halo 3 Invincible Allies
• Halo 3 ODST
• Halo 4 Invincible Allies