This is basically just a draft for now :oops: It shows how to slim down the "Data"-directory.

All my mods/tutorials only have offline in mind. In this case it can vastly speedup testing for modders. I definitely don't recommend it for online. Use at your own risk!!


advantages:

    blazingly fast (nearly like good old D2!)
    great for all tests with v1.15 that don't need HD (but also useful for UI-/Item-Modders!)
    core is only 2,2GB
    HD-GUI still working
    can probably be further optimized :)

disadvantages:

    no HD in-game graphics at all (black screen, but controls still work)
    core doesn't feature any music/sound

Tools used: Ladiks CascViewer, windows explorer

requirements: ~20GB free space on system drive (NVME-drive highly recommended!), patience.

First:Temporarily DISABLE realtime protection for better performance (this vastly increases the setup). Stop file-indexing and other taxing services.
Do the core setup on your first try (skip optionals / delete where mentioned).

quick rundown for now:
Start CascViewer, go to options and choose a workfolder on your systemdrive.

1. \data\global\
extract everything. Optional: \music (0,6GB) & \video (1,8GB), \sfx(=sounds, 150mb) (all legacy mode media)

2. \data\local\
extract everything except \video. Optional: sfx (=voice files, 0,5GB)

3.1 \data\hd\
extract \items, \missiles, \objects, \overlays, \ui and all json files in root

3.2 \data\hd\character\
extract subfolder \player\ and the monsters.json

3.3 \data\hd\env\
extract subfolder \weather

3.4 \data\hd\global\
extract subfolders \excel, \ui and all jsons from root. Optional: \sfx (0,5GB ), \music (music 1,4gb), \video (2GB) for sound, music, video in HD-Mode

4. Cleanup (windows explorer / file manager)

Delete folder \hd\global\ui\lobby (320MB).

Optional: Delete folder \data\\hd\global\ui\controller (650MB) (controller support). It's not really essential and only gives some very minor menu-graphics-bugs when not used.

Go to \data\data\hd: delete all "*.model" and "*.texture" files (9031 model, 3758 texture). You can simply search for them. This might take a while ;)
Delete (the now empty) "texture" folders. Delete all "*.lowend.sprite" files (0,5GB) from data\hd\global\ui.

You'll end up with hd(1,2GB), local(944MB) & local (133MB) taking only ~2,2GB of diskspace ~34.500 files (all optionals excluded).

5. finish
Now carefully replace(!) your hd, local, global by renaming/moving folders. Run your game via "D2R.exe -direct -txt" and have fun! :mrgreen: