My Hero Academia : The Strongest Hero compressed files

Extraction and unpacking of game archives and compression, encryption, obfuscation, decoding of unknown files
Drieow
Posts: 6
Joined: Thu Mar 17, 2022 1:37 am

My Hero Academia : The Strongest Hero compressed files

Post by Drieow »

I wanted to ask if it would be possible to make a quickbms script to decompress or decrypt those files, i could find plain flv files in the files of the game, but also encrypted assets (If more samples are needed i can give more).

It would be greatly appreciated to know if it's even possible to decrypt those ! Thanks in advance for your time !
Drieow
Posts: 6
Joined: Thu Mar 17, 2022 1:37 am

Re: My Hero Academia : The Strongest Hero compressed files

Post by Drieow »

I'm bumping while providing some more samples and also a file called md5_1.txt, with clear FLVs files that could maybe help to figure things out.
spiritovod
Posts: 719
Joined: Sat Sep 28, 2019 7:00 pm

Re: My Hero Academia : The Strongest Hero compressed files

Post by spiritovod »

Apparently the game is using simple xor on file headers, key is derived from keys table based on file type and probably something else, while some file types are not obfuscated. I've attached test script, which can extract most asset types - just use it on the whole folder. pkm are ETC2 RGBA compressed textures, they can be converted with PVRTexTool, Mali Texture Compression Tool or any other compatible tool. bank are fsb audio, should be playable with vgmstream. Not sure about the rest though.

Update: Script is updated with support for more asset types. Currently supported: png, jpg, etc2, lua, xml, bank, flv, conf, anim, materials and mesh files.
Last edited by spiritovod on Wed May 11, 2022 4:55 pm, edited 2 times in total.
Drieow
Posts: 6
Joined: Thu Mar 17, 2022 1:37 am

Re: My Hero Academia : The Strongest Hero compressed files

Post by Drieow »

Thanks a lot it works perfectly !
Drieow
Posts: 6
Joined: Thu Mar 17, 2022 1:37 am

Re: My Hero Academia : The Strongest Hero compressed files

Post by Drieow »

Any idea how to look at the mesh files by any chance ?
spiritovod
Posts: 719
Joined: Sat Sep 28, 2019 7:00 pm

Re: My Hero Academia : The Strongest Hero compressed files

Post by spiritovod »

@Drieow: You can create a separate topic with samples in 3D models subforum here or xentax forums. xmd format looks pretty simple, so maybe someone will help you with it. Though it doesn't contain rigging info - it's stored in other files, which are not covered by the script.
spiritovod
Posts: 719
Joined: Sat Sep 28, 2019 7:00 pm

Re: My Hero Academia : The Strongest Hero compressed files

Post by spiritovod »

Script is updated with support for more asset types. It also includes fix for previously covered types, such as lua and axmd (first byte in those files was incorrect).
Drieow
Posts: 6
Joined: Thu Mar 17, 2022 1:37 am

Re: My Hero Academia : The Strongest Hero compressed files

Post by Drieow »

Thanks for the update i'll be making a topic for the xmd files soonish. If you could help me understand what to send on the separate topic i'd guess anim files and xmd files.