The file in Sonic Mania (and the retro engine games like Sonic CD 2011 ) is essentially a packaged archive containing all the game’s assets: levels, sprites, sound effects, music, scripts, and configurations.
To extract/modify it, you’ll need :
| Tool | Purpose | |------|---------| | | Decrypt/decode the RSDK | | Mania Toolkit / ManiacEditor | Level editing, sprite replacement | | RetroED (older) | Basic extraction | | RSDK Tool (by Rubberduckycooly) | Extract/re-pack RSDKv4 | sonic mania rsdk file