Possible to Hex Edit 3DS Save Files?

Discussion in '3DS - ROM Hacking, Translations and Utilities' started by 19cookies, Feb 6, 2015.

  1. 19cookies
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    19cookies GBAtemp Fan

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    I apologize if this question has been answered before! :)

    Is it possible to hex edit 3ds save files?
    I've been waiting ages for Powersaves to put up codes for Harvest Moon Lost Valley and it just isn't happening.

    It's a great game but I get so bored trying to save up money for all the upgrades and just want a quick way of being able to afford them. Is this possible?
     
  2. storm75x

    storm75x Remember that thing I don't remember? Yeah, that!

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    Save files are encrypted. Using MT Card cheat should be way easier.
     
  3. 19cookies
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    19cookies GBAtemp Fan

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    Can I not just decrypt the save file using savedatafiler?

    I presume I can't use MT Card cheats with a Gateway? :P
     
  4. hippy dave

    hippy dave Butts Butts Megabutts

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    Yeah once you've extracted with sdf you can edit what you want. Just need to find the relevant data and look out for any checksums etc.
     
  5. 19cookies
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    19cookies GBAtemp Fan

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    Thanks! Just wanted to make sure it was possible before trying, I've done hex editing before but it was ages ago, not sure if I can remember how :P

    Edit: sdf doesn't seem to have the save file listed so I'm not sure how to decrypt it :S
     
  6. Lord M

    Lord M GBAtemp Advanced Fan

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    19cookies likes this.
  7. 19cookies
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    19cookies GBAtemp Fan

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  8. Lord M

    Lord M GBAtemp Advanced Fan

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    Give thanks for who make this tutorial, not to me :)
     
  9. 19cookies
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    19cookies GBAtemp Fan

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    Of course I'll thank them, but I wouldn't have found it without you! :P
     
  10. 19cookies
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    19cookies GBAtemp Fan

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  11. MichiS97

    MichiS97 "Leftist snowflake milennial"

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    You need to be careful though. Most save games have checksum integrity checks so editing values without fixing the checksum will end you up with a corrupt save file. Pulling this off is not that difficult though ;)
     
  12. 19cookies
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    19cookies GBAtemp Fan

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    Thanks for letting me know! Not had any problems so far but I know for the future :)
     
  13. hawkeye91

    hawkeye91 Advanced Member

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    Wow what game is that? Do you know any game that doesnt use checksum other than bravely default? I always failed editing games like rune factory, persona q and EOIV
     
  14. ChrisX930

    ChrisX930 Banned

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    same problem here.
    Found some variables for Rune Factory 4 in the savefiles, but after editing and reimporting with Savedatafiler, the Savegame is corrupted.
     
  15. Rurounik99

    Rurounik99 Advanced Member

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    MH4U does have extra encryption added by Capcom.
     
  16. ultrazonn

    ultrazonn Newbie

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    And so, how we can decrypt an hex edit correctly MH4U?
     
  17. Rurounik99

    Rurounik99 Advanced Member

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    According to some users, we need to find the encrypt/filter subroutine in exefs. We could try to make a editor based on mh4g exefs, or completely rewrite encryptor / filter to bypass capcom's copyright.