I'm working on decrypting a couple of .PNG files extracted from an .apk of a Chinese One-Punch Man mobile game. They're identified as .PNGs by Windows, but can't be opened by any software. HxD shows me that they have no .PNG IDs such as "IHDR" or "IDAT", so I assume they're pretty encrypted (or they're not even PNGs???). Each one says "SSKOSISNIUBILITY" at the top, not sure what it means.
53 53 4B 4F 53 49 53 4E 49 55 42 49 4C 49 54 59
18 1C 18 1C 1C 1C 01 00 06 06 0B 13 09 02 11 00
I've tried a couple BMS scripts with quickBMS to no avail. Since the game is made by FingerFun I tried using a BMS script for one of their other games (KOF'98 UM OL) to no avail. Looks like I need to figure out what kind of encryption it is before I start throwing things to see what sticks.
Here's a few example files: https://www.dropbox.com/s/imy674lcnzqcl9s/135.zip?dl=0
Any help would be appreciated. I'm pretty amateur when it comes to decryption, so just a BMS script or a name for the encryption style would suffice.