This is an SNES Utility that allows you to extract a subset of a ROM and save it to a separate file, or reinsert a chunk of ROM data back into a ROM file. Additionally, it makes use of Evil Peer’s re/decompression algorithm to compress or decompress chunks of a Chrono Trigger ROM (as CT uses a proprietary compression scheme, that is the only game for which the re/decompression works).

This is useful for things like sprite or tileset editing- you can pull out (and decompress, if necessary) the relevant ROM data, edit it however you like, and then reinsert it into the original ROM.

Included in the .zip file is a readme with an example usage, and a text file containing all of the known offsets in Chrono Trigger. READ THE README FIRST, please! If you don’t, it is very possible to corrupt your ROM file. If you’re careful, though, that won’t happen. Happy hacking!