Excession is the official mod uploader for MCC which allows you to publish your work to the Steam workshop. It is used for for all games in the MCC and is a separate download from the mod tools. It's not something you need to use until you're ready to publish your mod.

See the official documentation for help using it.


July 2023

  • Added support for gamepad preset mods.

December 2022

  • Fixed a crash where pressing remove on an empty directory in configure would crash.
  • Now properly recognizes the minimum package of the game client and no longer errors when changing the app version.
  • Updated latest version number.
  • New icons.
  • Upload screen no longer uses title field when it should have used description field on submit.
  • Auto-tags items with the game engine (if there is one), and the game contents like SP or MP it contains (if any). This allows filtering in the workshop.
  • Upload screen includes a Change Log text box when uploading updates to existing items.
  • Upload screen includes a mod folder path and notes that all files in that path will be included in the upload.
  • Upload screen enforces the 1 MiB limit on preview images.
  • Upload screen relays messages to the user if they likely exceeded their Steam Cloud quota.
  • Errors now logged when there are missing map files for the scenarios defined. The MCC UI will also ignore such invalid content.
  • Fixed custom campaign mission names not showing after mission number.
  • Fixed a crash and "save all failed" errors when saving background videos.
  • Fixed crash when exporting Map Info BLF when map title is 32 characters or longer.