Downgrade Patches

Want to use a mod for a version you don't have? Look no further with these downgrade patches! Includes 1.01A to 1.04 patches for the Steam version. Doesn't contain patches for the Switch, PS4, or itch.io (and the Switch 2 hasn't been hacked yet so that's a no go as well).

I haven't tested these myself. I made these to test out a feature of GM3P I was working on.

"What Version Do I Need?"

Download the .zip referring to the version you have, and use the patch named after the patch you need.

For what Chapter version refers to what version of Deltarune, refer to this terribly screenshotted table I made in Excel 2007:

or go to this Google Sheet: https://docs.google.com/spreadsheets/d/18a66wox9sgiS_Fr5htSfMqkzoRZVMkxSM4KN0ZL-ND0/edit?usp=sharing

The Deltamod/G3M package will apply v1.04. For other versions of Deltarune or when using a version of Deltamod/G3M that doesn't support add-on mods, follow the text-based guide below.

Text-based guide:

For patching from v1.06 or v1.07D:

For G3M: 

1. Download the .zip file that matches the version of DELTARUNE you have (for Ch3 v0.0.098, that would be v1.04)

1. Extract the .zip folder containing the patches and have a Steam copy of DELTARUNE ready (these patches don't support Switch, itch.io, or PS4 copies)

1. (optional, but recommended) copy the DELTARUNE folder to another place for backup.

1. Launch G3M and click "Library" and then the wrench icon in the filter bar, this will bring up the GUI for G3MTool.

1. Hit "Patch" and then change "Action" to "Apply"

1. Select the data.win from your vanilla game as your "original file"

1. Select the patch you need, which will be by Chapter Number (with 0 being the root) -> Version (of the overall Deltarune version, not the Chapter version) in the extracted folder as the "xdelta patch"

1. Hit "Run"

1. Repeat Steps 5-8 for all 4 or 6 data.wins, rotating what data.win you select in Step 4.

For GM3P or Deltapatcher:

1. Download the .zip file that matches the version of DELTARUNE you have (for Ch3 v0.0.098, that would be v1.04)

1. Extract the .zip folder containing the patches and have a Steam copy of DELTARUNE ready (these patches don't support Switch, itch.io, or PS4 copies)

1. (optional, but recommended) copy the DELTARUNE folder to another place for backup.

1. (7-zip required) Right-Click on the g3mpatch(es) you want to patch. If on Windows 11, select "Select more options". Click on "7-zip -> Open archive". Enter the XDelta folder in the archive and extract the file there.

1. follow the guide for the Version (of the overall Deltarune version, not the Chapter version) in the extracted folder as the "xdelta patch"

1. Hit "Patch"

1. Repeat Steps 4-6 for all 5 data.wins, rotating what data.win you select in Step 4.

For GM3P:

1. Drag and drop the DELTARUNE folder when it asks you for vanilla.

1. When it asks you how many mods you would like to patch, enter 1.

1. Drag and drop the patch you need, one chapter at a time, which will be by Chapter Number (with 0 being the root) -> Version (of the overall Deltarune version, not the Chapter version) in the extracted folder.

1. When it asks for a modtool, enter "noCombine"

1. When it asks to enter a modpack name, enter whatever you like.

1. The resulting data.win would be in output/result/*modpack name*/*chapter number*/data.win under the GM3P folder. Replace the respective data.win in the DELTARUNE folder with it.