Mod Workspace Setup
To decrypt the the game and get a clean repository of all of the raw assets, first you must have Oneloader installed on your copy of the game.
Open the game and go to the options menu. You should see a new tab labeled "Mods"! An image showing the tab is seen below.
Here we are focusing on the "Decrypt" label. Here is an explanation of what everything here does:
Decryption Mode- Decides what the game will decrypt. "Everything" decrypts the base game with mods, "Base Game" only decrypts the vanilla assets, and "Only Mods" decrypts only the currently enabled mods.
Generate as Rpgmaker project?- Decides whether or not an Rpgmaker project file will be generated. Unless you're only doing basic asset editing, you will want to select "Yes" on this.
Start decryption- Clicking the button will start game decryption with the settings. It may take a while, so be patient! Progress is shown on a blue bar at the top of the screen. The decrypted assets will be in the OMORI game folder, under a new folder named "www_playtest_xxxxxx" or "www_decrypt_xxxxxx", depending on whether or not you chose to generate an Rpgmaker project file.
Opening the game in RPGMAKER MV is as simple as opening the project file found in the "www_playtest_xxxxxx" folder through the application.
After editing the game's data and assets from the "www_decrypt_xxxxxx" or "www_playtest_xxxxxx" folder, you can package your mod into a zip for use by running Bundletool. The application should walk you through the process.