The mod tools, also called the editing kits, are the official releases of tools used to create custom content for the Halo games in the MCC. This site also covers the HEK for Custom Edition since its usage is similar to the Halo: CE Mod Tools, though it is not distributed via Steam.

Each game has its own set of mod tools which, although similar, follow the evolution of Halo's engine over time and include the resources specific to that game. These tools are updated versions of the same internal tools Bungie's artists and level designers originally used when developing Halo. You can use them to modify existing content or create entirely new content. A separately installed program, Excession, publishes mods to the Steam workshop.

Installation

1. Install Steam if you haven't already. Windows Store is unsupported.
2. Ensure you own MCC and corresponding DLC for the game you want to mod on Steam: H2, H3, ODST, Reach.
3. Download the tools using Steam: H1, H2, H3, ODST, Reach.
4. Once the tools are done downloading you can find them in your library in the "tools" section.
5. Right click the entry for the mod tools, and select Manage > Browse local files from the context menu. This will open the folder where the tools are installed.
6. Run the <game> (Extract).bat file - this script will extract all the assets the tools rely on like shader sources and tags.

Pin the installation folder in Explorer's quick access or create a shortcut to it, since you will need frequent access to these files and it's easier to run the tools from explorer than through Steam's launcher.

You should also add your mod tools folders to the Windows Defender exclusions list. Tools like Sapien and Standalone will load faster.

Installing updates

Steam updates to the tools are unlikely to occur again now that development has halted, but they will not overwrite your tags. Instead, the included .7z archive will be updated with any needed stock content changes.

1. Back up any stock tags you modified.
2. Re-run the extraction .bat file and replace all files.

Tools overview

The following tools come with each game's mod tools, sometimes with build type variants:

• Tool (tool.exe) is a command-line utility. Use it to import source data into tag format and build distributable map files.
• Guerilla, and later Foundation, are tag data editors. Use them to modify and create tags.
• Sapien is a visual scenario and scenario_structure_bsp editor, sort of like Forge. It's used to populate levels with objects, place multiplayer objectives, set up AI encounters, and assign environmental effects like weather. It is not used to model levels.
• Standalone or Tag Test (halo_tag_test.exe) is a build of Halo which loads from tags rather than maps. Use it to rapidly test and debug levels without having to build them for MCC.
• ManagedBlam.dll is a library present for H3+ which allows programmers creating custom tools to work with tag data compatibly.

Another tool, Excession, is installed separately and is needed to publish mods to the Steam workshop. Depending on your needs you will probably want more software, like Blender for creating 3D models and Osoyoos as a convenience launcher.

Files overview

The mod tools come with a lot of files and folders, but some important ones are:

• The data folder is where you put source data that you want to convert ("import") into tag format, like textures, models, and animations. You create these files using external software, like Blender for 3D assets. The layout of folders here will match the layout under tags:
• The tags folder is where you find tag resources for the game's stock content. These resources are enough to rebuild stock levels and can serve as examples for your modding or the basis of a remix. You will create custom tags under this folder too.
• The maps folder may not exist initially, but is where Tool puts maps built from your tags when requested.

Using custom content paths

The H1A-EK and H2-EK tools support overriding content paths so you can work on multiple isolated projects. H3-EK doesn't support this and neither do legacy editing kits (HEK and H2V).

• The data directory can be set using the -data_dir <path> argument.
• The tags directory can similarly be set using the -tags_dir <path> argument.
• The game root directory, used when compiling maps and finding resource maps, is set using -game_root_dir <path>.

If no content path is given the tools fallback to using the data, tags, and maps subdirectories of the current directory respectively.

Here are some examples:

# packages the tutorial map using assets located in the "hek_tags" tags directory
tool -tags_dir hek_tags build-cache-file levels\test\tutorial\tutorial classic

# launch Sapien using your custom tag+data set located in "E:\my_custom_tagset\"
sapien -tags_dir "E:\my_custom_tagset\tags" -data_dir "E:\my_custom_tagset\data"

# Edit old HEK tags using the new Guerilla release
guerilla -tags_dir "E:\Program Files (x86)\Microsoft Games\Halo Custom Edition\tags"

# Test your custom tagset in the standalone build
halo_tag_test -tags_dir "E:\my_custom_tagset\tags" -windowed

# also works for h2
halo2_tag_test -tags_dir "F:\custom_h2mcc\tags"