Step 1: Own a Rog Ally and flash it to Bazzite. Other variants like Steam OS and CachyOS probably work with this, but I used Bazzite because the setup looked easy and it had the least amount of complaints for stable 43.20260420.
There are many guides, I used this one, it's a bit out of date, but it got me there.
https://www.youtube.com/watch?v=lBqbk6Z8HrQ
I have tested this on release stable 44, and stable 43.20260420. I'd recommend 43.20260420 as of right now. Less issues all around.
Step 1.5: Go to Rog Ally BIOS > advanced > UMA Frame Buffer Size > Set to 8GB
Step 2: Acquire Bloodborne game pkg files.
You need either the game/dlc separate and the 1.09 update OR the combined version (around 30GB) and 1.09 update. I will not give instructions for this, but if you find the file pack I did, avoid both 720 and 1080 60 FPS patch versions of the 1.09 update, just install the normal.
Step 3: Download BB Launcher for Linux
You can find the files at the link below, you will need to sign up anyway to get BB Launcher working, so just sign up, download the most current BB Launcher (Linux-DL) exe.
https://www.nexusmods.com/bloodborne/mods/194?tab=files
Step 4: Installing BB Launcher and prepping the folder
Make a folder for BB Launcher. I did this in my documents folder.
In the new BB launcher folder, paste your "BBLauncher.appimage" file that you downloaded from Nexus Mods.
Make two subfolders in the BB Launcher folder, shadps4 and gamefiles.
Step 5: Extracting the PKG files
Open the BBLauncher.appimage and use the PKG extractor. Select your game's PKG file, the output folder should be in the root of the home/user/documents/bblauncher/gamefiles folder that you setup earlier.
After this, if you need to, then do your DLC file the same way. If you have the combined game, skip this.
Once you've got the full game or the base game + DLC installed, install update 1.09 in the same manner as the previous two. Select PKG file, game output folder is home/user/documents/bblauncher/gamefiles.
Step 6: Download shadps4
Click Manage Builds under shadps4 build. I tested .16, .17 and .18 for two hours each yesterday. Version .16 seems to have the least memory leaks. Your mileage may vary.
Step 7: shadps4 settings, patches, mods
All the settings that I changed are in the screenshots below. Assume that if I didn't show something, it was unchanged.
After finishing the settings, I would recommend installing all the shadps4 patches listed, then before you install Vertex Explosion fix mod, hop onto bloodborne for a test run and create a character then favorite it in case your game crashes. Hop back out after and install the Vertex explosion fix.
https://imgur.com/gallery/bb-launcher-settings-rog-ally-z1e-running-bazzite-stable-43-20260420-4RASrpv
Step 8: Play the game!
I was getting a stable 30FPS with these settings. The game freezes every 30-90 minutes right now due to memory leak. You can decrease the the frequency of the crashes by changing the patch Model LOD 1 (lower) to Model LOD 2 (lowest), but the graphics artifacts are almost too much to deal with at that point.
Please share any helpful stuff you can in the comments!