Create a new project through RPG Maker MV.
Copy the files of TDE (or whatever game you want to mod) into the project's folder.
You may have to decrypt the files, I know I had to for this game or else the custom assets wont appear.
You must be registered to see the links
If done properly you should be able to see the assets for event+map and the different levels on the left side.
As for adding in a new character, the dev made an original (with all scripting and stuff) and a copy that you can copy+paste and they will follow the same behaviours.
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