Homebrew Saturn emulation using Cotton/Guardian Force testing and debug

[instereo4]

Guys, anyone knows if is possible to run Castlevania Symphony of the night Ultimate (the japanese edition with Medusa Team Patch). I tested the game without patch and worked (the akumajo dracula sotn jpn version) but after applied the patch didnt work, the software crashes. (I tested with bat scripts to convert saturn to nsp). But in pc emulator using jpn saturn bios it worked.

 

[IllusionMaster17]

Essentially, "COTTON2" is not a perfect Saturn game emulator, but a defective version of "SSF" emulator. For example, there are problems such as "bios" files cannot be called and compatibility is too poor. As for the many games you mentioned that cannot be perfectly emulated, most of them are still problems with settings. But because the settings of each game are different, I should not be able to give you a perfect solution. But I may be able to provide some game "ini" configuration files if you need it.

So Cotton2 is simply an "it just works" emulator. Had to see it coming.
And if you have the .ini files to make some games work, can you send them please? I'm fine with it, personally I don't need of 100% accuracy to play it full.

 

[hotcofe]

So Cotton2 is simply an "it just works" emulator. Had to see it coming.
And if you have the .ini files to make some games work, can you send them please? I'm fine with it, personally I don't need of 100% accuracy to play it full.

Can you tell me which game configuration files you need? I'll check if I have them here. If I do, I'll share them with you.

 

[Slayer14]

can someone that knows tell me how to change the rom name
i made a castlevania symphony of the night nsp but when it installs
the cotton tribute name it still there and would like to change it to
the symphony of the night title...anyone?

 

[emcintosh]

can someone that knows tell me how to change the rom name
i made a castlevania symphony of the night nsp but when it installs
the cotton tribute name it still there and would like to change it to
the symphony of the night title...anyone?

IIRC setting a name for the game is a step in the Ultimate Switch Hacking Script's Saturn injection function.

 

[ThePanda]

can someone that knows tell me how to change the rom name
i made a castlevania symphony of the night nsp but when it installs
the cotton tribute name it still there and would like to change it to
the symphony of the night title...anyone?

You can use the public build of CaVE to create these. It’s an easy step by step GUI with various customization.

Homebrew  Thread 'CaVE Database Manager - A SNES, NES, N64, Genesis Switch Online modding App'

Nov 3, 2019

NOTICE: This thread is NOT ABOUT RETROARCH or other fan emulators. Please do not discuss them here. Search for the other threads that ARE about it. This is just for the Nintendo Switch Online apps, CaVE, SFROM Tool, etc.

We don't care if or when it's better. We don't need you to tell people RA exists every time some game doesnt work. Assume people know as much, and just stay on topic.

Also, don't use pre-made game packs. I work to hard on these things for my work to be bastardized, and for my efforts to be completely ignored and obscured to the people benefiting from my work with...

• DarkAkuma
• Replies: 1,921
• Forum: Nintendo Switch

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[Slayer14]

You can use the public build of CaVE to create these. It’s an easy step by step GUI with various customization.

this does the job but sadly makes the games to go slow sometimes
Castlevania Symphony of the night in one converter runs good and in this one runs slow
i guess it depends on the converter sadly the converter i am using has and issue with adding the name
to the main nsp.

 

[IllusionMaster17]

Can you tell me which game configuration files you need? I'll check if I have them here. If I do, I'll share them with you.

Nice!
Here are the games so far:
- Fighters Megamix
- NIGHTS
- Sonic R
- Saturn Bomberman Fight
- Sonic Jam
- House of the Dead

 

[hotcofe]

Nice!
Here are the games so far:
- Fighters Megamix
- NIGHTS
- Sonic R
- Saturn Bomberman Fight
- Sonic Jam
- House of the Dead

The compressed file includes the configuration files of "Fighters Megamix", "bomberman" and "nights". Remember to rename them before use. I have not made other games, so I cannot provide them for the time being. But you can use the setting files of other games for testing. As far as I know, the configuration files of many games are universal. I hope it will be helpful to you.

 

[Slownic]

So, I can't wrap my head around how to make this work since I can't seem to make the Ultimate Switch Script Saturn Injector to work and I can't seem to understand how to make the inject work generally, since there have been so many updates.

I just wanted to play Policenauts, but I don't understand which procedure I should follow, can somebody help, please?

Thank you so so much in advance!

 

[fst312]

So, I can't wrap my head around how to make this work since I can't seem to make the Ultimate Switch Script Saturn Injector to work and I can't seem to understand how to make the inject work generally, since there have been so many updates.

I just wanted to play Policenauts, but I don't understand which procedure I should follow, can somebody help, please?

Thank you so so much in advance!

Hey I’ve been watching this thread for along time and I’m not sure if anyone actually knows the exact page here to follow. I know there’s that important post thing on top of page but really page 74 should be added to that. Here you go if you didn’t see this with all these pages on this thread. Hope this helps.
Edit
Trying to paste link doesn’t work to page for some reason. It just shows front page of thread.

 

[IllusionMaster17]

The compressed file includes the configuration files of "Fighters Megamix", "bomberman" and "nights". Remember to rename them before use. I have not made other games, so I cannot provide them for the time being. But you can use the setting files of other games for testing. As far as I know, the configuration files of many games are universal. I hope it will be helpful to you.

Greetings!
I've been making some testes with the config files and I have two things to say:
1. The NIGHTS config seems to be corrupted/broken. All text appears as japanese hiragana gibberish with symbols, while the other 2 work great. By the way, thank you so much!
2. I've been trying the Fighters Megamix ini file in other titles such as Virtua Fighter Remix and 2 and seems to work good with those too.
I'll keep trying some other games. Bye!

 

[YoraeRasante]

Hey there. I'm kinda new to injection, so I may be doing something wrong?

I saw a video and tried following the instructions, but despite having already updated the Ultimate Switch Hacking Script it still asks to update when I set it to start the actual injection (6 then 16) it says it needs to update again, and... freezes at some point of the update.
Judging by how it creates a "failed updates log" I'm guessing it is not being able to update for some reason.
(the video also at some point needed some keys but the link on it to where to find them was broken, and the invite to a discord with the files was not working anymore)

I also tried using Yuzu to unpack the NSP of Cotton2 to try the original method, yet there is no bue/bin files...

 

[markn12]

anyone try shining force 3 ?

EDIT

So shining force seems to run into the same issue you get with Yaba on PC and the switch. After or when combat starts the game freezes. This seems to be an emulator issue and not a game specific issue though because the game works with beetle saturn on PC. I have yet to find a fix for the switch.

Post automatically merged: Jul 30, 2025

so i had a thought. Does Cotton work on switch 2 ? If so wouldnt it be possible to use mig switch and saturn nsp generator to put a saturn nsp on the mig switch and play it on the switch 2

 

[Olinnae1]

Guys, anyone knows if is possible to run Castlevania Symphony of the night Ultimate (the japanese edition with Medusa Team Patch). I tested the game without patch and worked (the akumajo dracula sotn jpn version) but after applied the patch didnt work, the software crashes. (I tested with bat scripts to convert saturn to nsp). But in pc emulator using jpn saturn bios it worked.

I'm also trying to get this to work myself, have you had any lucky?

 

[Slayer14]

I'm also trying to get this to work myself, have you had any lucky?

you need Saturn_2_NSP_v1.3
https://www.mediafire.com/file/ld8qvgryeptfnog/Saturn_2_NSP_v1.3.rar/file

 

[dragonz]

you need Saturn_2_NSP_v1.3
https://www.mediafire.com/file/ld8qvgryeptfnog/Saturn_2_NSP_v1.3.rar/file

I downloaded this but I don't see the "Create_Saturn_NSP_v1.3bat" file anywhere.

 

[Olinnae1]

I downloaded this but I don't see the "Create_Saturn_NSP_v1.3bat" file anywhere.

First open the 'dependance' folder > run and install the python executable in there, when you do make sure you check the box that says 'Add Python to PATH,' if you do not it will not work > once that finishes installing, back in the 'dependance' folder double click the 'install pillow' file, this will install itself automatically with no more additional input needed from you > Once that is done, you will need your prod.keys file and keys.dat file from your switch in the 'tool's folder before you can run it, (the keys file must be a .ini format. I just renamed mine and it worked. So "keys.ini" is what it should look like.) then you should be good run the program by running the "Saturn_2_NSP_v1.3.py" file in the main folder of the download.

I'm not sure exactly how the rules work here but just to be safe I cannot tell you how to get your prod.keys or keys.dat files. you will need to figure that part on your own. The info isn't hard to find though

I have not made or tested any NSPs yet, once I figured all this out I came to respond to you, but now you can at least run the program now to make/test your own games. Let me know how it goes!

 

[dragonz]

First open the 'dependance' folder > run and install the python executable in there, when you do make sure you check the box that says 'Add Python to PATH,' if you do not it will not work > once that finishes installing, back in the 'dependance' folder double click the 'install pillow' file, this will install itself automatically with no more additional input needed from you > Once that is done, you will need your prod.keys file and keys.dat file from your switch in the 'tool's folder before you can run it, (the keys file must be a .ini format. I just renamed mine and it worked. So "keys.ini" is what it should look like.) then you should be good run the program by running the "Saturn_2_NSP_v1.3.py" file in the main folder of the download.

I'm not sure exactly how the rules work here but just to be safe I cannot tell you how to get your prod.keys or keys.dat files. you will need to figure that part on your own. The info isn't hard to find though

I have not made or tested any NSPs yet, once I figured all this out I came to respond to you, but now you can at least run the program now to make/test your own games. Let me know how it goes!

Great tutorial, thanks! I’ve never really had any major issues with Saturn_2_NSP_v1.2—well, a few minor ones—but overall, I've been able to get all my games running smoothly (aside from the fact that most run better when overclocked). I even got the latest Castlevania SOTN (Ultimate) and Princess Crown working without a hitch. So, I’m mainly interested in version 1.3 as a backup. If you manage to get a successful NSP working with it, let me know!

Post automatically merged: Aug 21, 2025

Make a NSP for the game CD1 play and save
Make a NSP for the game CD2 run it once and quit
Use jksv and dump the save from game cd1 and game cd2
Import the save from game cd1 on game cd2
I haven't tested it but maybe that should work

Hey @princessvini , thanks for sharing your method—really appreciate you laying it out.

I want to test this myself and was wondering if it could be simplified a bit. Would this work just as well?

Create NSP for Disc 1 → Play → Save
Create NSP for Disc 2 → Launch once → Quit
Use JKSV to dump Disc 1’s save
Inject Disc 1’s save into Disc 2’s save folder using JKSV
Launch Disc 2 → Continue your game

Not trying to question your approach—just exploring the cleanest way to get it working.

 

[Olinnae1]

Great tutorial, thanks! I’ve never really had any major issues with Saturn_2_NSP_v1.2—well, a few minor ones—but overall, I've been able to get all my games running smoothly (aside from the fact that most run better when overclocked). I even got the latest Castlevania SOTN (Ultimate) and Princess Crown working without a hitch. So, I’m mainly interested in version 1.3 as a backup. If you manage to get a successful NSP working with it, let me know!

Post automatically merged: Aug 21, 2025

Hey @princessvini , thanks for sharing your method—really appreciate you laying it out.

I want to test this myself and was wondering if it could be simplified a bit. Would this work just as well?

Create NSP for Disc 1 → Play → Save
Create NSP for Disc 2 → Launch once → Quit
Use JKSV to dump Disc 1’s save
Inject Disc 1’s save into Disc 2’s save folder using JKSV
Launch Disc 2 → Continue your game

Not trying to question your approach—just exploring the cleanest way to get it working.

I got Alone in the Dark to work as a test run but haven't tried anything else because I started working on something else (the thing below)

Bro, I have been pulling my hair out trying to get SOTN Ultimate working, the "Castlevania - Nocturne in the Moonlight Ultimate Edition Hack" right? I've tried everything, it's why I wanted v1.3 to see if that would work, it didn't. I can make and install the NSP, I can launch it on switch and the emulator starts with the controls screen, but then crashes as soon as the actual game tries to start. Every single time no matter what I try, Could you help me out with that? I am very interested in Princess Crown and it's English patch as well. We can DM if that will make it easier, I am desperate lol