SciresM

If anybody is interested in save hacking, I figured out Awakening's save compression/checksum today. It's pretty simple. Global (global data file) is a single compressed archive, Chapter# files are some decompressed data and then a compressed archive. Compressed archive structure is as follows: 4-byte magic value 0x434F4D50 ("PMOC", or "COMP") 4-byte "Compression Type" (this is 02 for all Awakening saves I've encountered). 4-byte "Size of decompressed data" 4-byte checksum, where checksum is the CRC32 of all concatenated decomprsesed data in the file (for Global, it's crc32 of the decompressed archive, for Chapter# it's crc32 of the initial data and the decompressed archive). Compressed data, depending on compression type value. Compression Type is always 02 for Awakening saves, which corresponds to 8-bit huffman compression. I verified all this by decompressing a save, editing a character's skills, then recompressing and fixing the checksum. Save loaded fine. I might make a tool to auto-decompress and recompress saves if anyone's actually interested.

I intend to make a .ppf path to make the menus english, if possible.

I'd be happy to turn menu translations into a patch.

It is not possible:

Was your download really 24666 blocks? I pre-loaded the game right now, and my download was 1602940928 bytes (~1.5 GB) -- significantly smaller than the ~3 GB you're listing. (It's possible that the pre-load only loads the content not specific to either White Kingdom or Black Kingdom, and the remaining ~1.5 GB is downloaded as DLC when you get to the relevant parts of the game.)

Yes, a complete copy of the game is downloaded to the SD card. No, this does not mean it can be hacked -- technically, sure, it can, but not in any of our lifetimes. The way pre-loading works is that a complete copy of the game is downloaded before release date. On release date, the eshop publishes an 0x10 byte value called the "external seed" -- this value is used to calculate the decryption key for the game, and there's no way to get into the contents of the game without that value. When you download the "small update" on release, your 3ds is really just putting that 16-byte value into its NAND. Because the eshop doesn't publish that 16-byte seed until the release date, nothing can be done to get into the game before release even though the game's downloadable. You'd have to brute-force a 128-bit value -- this is pretty much impossible to do in any meaningful timeframe.

I just dumped and decrypted the US FE:A demo. Anyone who wants it, shoot me a PM and I can send the rom contents your way.

Awesome to see this getting used -- Fire Emblem: Awakening was actually one of the games I used to test the program before releasing it :) (It's the only one I know of with Japanese filenames).

If anyone wants to take a look at the extracted DLC contents, shoot me a PM -- I went through the process of decrypting/extracting all of them earlier tonight.

Just a note, the tool actually opens romfs binaries, not ROMs -- "ctrtool -x --romfs=romfs.bin Decrypted_Game.3ds" should do.