From Sonic Retro

Sonic Heroes 1 Archive Editor.png
Category: Archive editor
Supported Games: Sonic Heroes, Shadow the Hedgehog
Credits: MainMemory

HeroesONE is a tool and library for reading and writing .ONE files from the PC and console versions of Sonic Heroes and Shadow the Hedgehog. It was written by MainMemory in C#. When the Reloaded project debuted, the new editor (also designed to alter the archives from the said games, but with faster PRS compression/decompression methods) was written by Sewer56 as a replacement of this editor.