Install UndertaleModTool

About UndertaleModTool

The most complete tool for modding, decompiling and unpacking Undertale (and other GameMaker games!) Main Features: - Can read every single byte from the data file for latest versions of Undertale, Deltarune, and most other GameMaker games, and then recreate a byte-for-byte exact copy from the decoded data. - Properly handles all of the pointers in the file so that if you add/remove stuff, make things longer/shorter, move them around, etc., the file format won't break. - An editor which lets you change (almost) eve...

What's new in 0.9.1.2

This is the 0.9.1.2 UndertaleModTool release, for 64-bit Windows. Downloads can be found at the bottom of this release. ("UTMT_CLI" is the command-line interface version with no GUI, supported for Windows, Ubuntu, and macOS.) Changelog Note: This is a patch release. To see the changes in major release 0.9.0.0, click here. To see the changes in minor release 0.9.1.0, click here. Changed - Multiple dependencies updated, including some mostly-irrelevant security patches in ImageMagick. Fixed - Fixed Debug.csx not supporting updated versions of DELTARUNE Chapter 5. - Fixed tile instance IDs not being assigned by the project system, which could lead to strange issues and occasional crashes in-editor. - Fixed the CLI version number not being correct. Full Changelog: 0.9.1.1...0.9.1.2

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