SALT Team recently released 2 new secondary 3DS savegame exploits!

Game	Exploit	US Firmware	EUR Firmware	JP Firmware
Pokemon Super Mystery Dungeon	supermysterychunkhax	>=9.9	>10.2	>=9.9
VVVVV	(v*)hax	>=9.0.0-7	>=9.0.0-7	>=9.0.0-7

Prerequisites:
Exploit Game - Can be physical or digital.
Homebrew Launcher Access - You'll need to be able to get to this at least once, or do this process on someone else's 3DS that does have this.
Internet Connection on your 3DS - Easy.

Install:
0. If you don't know your 3DS's firmware, go into the system settings, and look at the bottom right corner of the top screen. You'll need to know exactly what this says, so feel free to write it down.

1. Download the 3DSX installer from here, and extract it to the root (Not in any folders) of your SD Card.

2. Put your SD Card into your 3DS, and boot into The Homebrew Launcher using your preferred method. Launch the installer for the exploit that you've chosen.

3. Follow the installer instructions.
If you have an old 3DS or a 2DS, select Old3DS for the firmware.
If you have a new 3DS, select New3DS for the firmware.
For the version number, enter exactly what you saw in step 0.

4. Let the installer download the appropriate payload and install it. You don't have to do anything.

Now, the exploit has been installed to your save, and the next time you boot up the game with the hacked save, The Homebrew Launcher will boot instead.

If a system update is released that you want to update to:
1. Hold select while booting the game.
2. Select Update *hax payload, and enter the new system version that you will update to.
3. After letting the updater run, now you can update your 3DS.

If you wish to wipe your save:
1. Hold select while booting the game.
2. Select Clear savegame.

https://smd.salthax.org/
http://vvvvvv.salthax.org/

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Updated the main post to include (v*)hax, the instructions are now more generic.

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Well, OoT3DHax also has to be updated when your firmware is updated, right?

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