The decompiled source code for the popular video game Undertale has been posted to GitHub. This decompilation contains what appears to be all of the game’s assets, including its images, scripts, and audio files. It is not know who decompiled the source code, but it is suspected that a user named Silica was involved in the release of this source code. BleepingComputer has attempted to contact Undertale developer Toby Fox and Silica, but have not received a response at this time.
Source: https://www.bleepingcomputer.com/news/gaming/decompiled-undertale-rpg-source-code-released-on-github/