Bathaxx is an exploit found in the game LEGO Batman: The Video Game. The exploit was made by Team Twiizers & lewurm.
LEGO Batman: The Video Game
NON-SDHC SD Card formatted to FAT(32)
Something to load (like the Hackmii Installer). Place the boot.dol/elf in the SD card root.
(Official Video guide here: http://www.youtube.com/watch?v=g4paz0Z9QYY)
0. Play the LEGO Batman game at least once and back up the save file to a safe location.
1. If there is a "Private" folder on your SD card, rename it to Privateold (or something else).
2. Download the Boot.dol/elf to execute (for example the Hackmii installer, the boot.elf is in the hackmii_installer folder so you can copy it from there). Place it in the root of the SD card (this means: not in any folder).
3. Download the Bathaxx pack and place the Private folder from the Zip in the SD card root (where the original private folder was).
4. On you Wii, go to the Saves management (Wii Button -> Data Management -> Save Data)
Remove the old LEGO Batman save on your Wii if it's still there (you should have it backed up by now)
Copy the Bathaxx save file to your Wii console (there's one for each region, you can copy them all, but you only need the one for the region of your LEGO Batman game).
5. Boot the LEGO Batman game.
In the game, load the save file.
You will be in the Batcave. Go to the bottom right and take the elevator upwards.
In the Hall, go up and take the door in the up left (going to Wayne Manor).
On the Character select screen you get, choose the character on the bottom row (to next-to-last character on the list).
The exploit will do it's thing now.
Additional Hackmii installer steps:
6. You will see a Scam warning screen.
Wait for the message at the bottom to appear, then press 1.
7. You will see a screen like this one:
Depending on your Wii, it will show different things behind BootMii:.
If you see Can be installed, you can get BootMii as boot2 (which gives the best brick protection there is).
If you see Can only be installed as an IOS, you can only get BootMii as IOS (which will give you NO brick protection on its own).
Press A to continue.
Now we get to the main menu, where we can install everything.
First install the Homebrew Channel (choose Yes, continue).
The Homebrew Channel will now be installed on your Wii.
Optional (Recommended) Steps: Installing BootMii
BootMii is a helps greatly with Brick protection and it is recommended to install it.
It is not required however.
These steps don't work on WiiU
8. In the HackMii main menu, choose BootMii... and press A. You will get another menu.
9. Before BootMii will work, we need to prepare our SD card, so do that first with the third option.
10. Install BootMii as IOS. This will always work.
11. If you're one of the lucky winners, choose install Bootmii as Boot2, then Yes, continue and let it install.
Once you're done, return to the Main menu and choose Exit. It will launch the Homebrew Channel. You can press Home to bring up a menu and reboot the console.
12. Don't forget to restore your old private folder if you had one!
If you installed BootMii (Wii only)
If you installed BootMii, regardless whether it was as boot2 or IOS, it is recommended you use it to create a NAND backup. This backup can be used to restore the Wii to a working state in case you brick it.
You can learn about launching BootMii and making a backup on the BootMii page.
If you installed BootMii as Boot2, the BootMii menu will appear every time you boot your Wii.
If you don't want this, rename/move the "bootmii" folder on the SD card.
Alternatively, you can enable Wii menu auto-boot in the configuration file.
So, what's next?
It mostly depends on what you want to do.
I want to run basic homebrew applications:
I want to load backup games from a USB drive, install WADs:
=> Continue on to install a cIOS which will allow you to use these more advanced apps.
I want to change the system menu theme (Wii only, will brick WiiU):