Help:Setting up tools

Breath of the Wild uses a very flexible game engine, so many aspects of the game can be configured with files. Since BotW uses a lot of custom formats, special tools are required for editing them.

Common requirements


Many of the tools for these formats require Python 3.7+ (64 bit version) to be installed.

On Linux, Python 3 is surely already installed. Just make sure you have a recent enough version (3.7+). Ubuntu 16.04 and Debian stretch are too old; the latest Ubuntu LTS (18.04) and rolling distros such as Arch and Debian sid have 3.7+ in their repos.

For Windows users: Visual C++ redistributable for Visual Studio 2019

Several tools require the 64-bit Visual C++ redistributable for Visual Studio 2019 to be installed. To be clear, Visual Studio is not required.

Failure to install the redistributable will cause several Python tools to fail with the error "ImportError: DLL load failed".



Many files in the game are compressed with the Yaz0 format. Compressed files generally have the letter s prefixed to their file extension. Use wszst to compress or decompress these files.


AAMP is used for configuration files, such as actor parameters, the world configuration (climate, lighting, ...), etc. Convert them to an editable format (and back) with aamp. Wild Bits can also edit AAMP files.

Note: Unlike most other files, AAMP files are exactly the same on both Wii U and Switch.


BYML files contain game parameters for actors, map units, etc. Convert them to an editable format (and back) with byml-v2. Wild Bits can also edit BYML files.


BFRES files contain the game's animations, models and textures. The format is different on and on Switch and Wii U. These can be edited on Switch and Wii U using Switch Toolbox (this tool is still under active development and receives very frequent updates, so expect some bugs in some features). Tutorials on another, older method of editing these for (Wii U only) can be found in Fooni's Tutorials.

  • .sbfres files contain models.
  • .Tex1.sbfres files contain textures (Wii U).
  • .Tex2.sbfres files contain mipmaps for textures (Wii U). They can be edited with Switch Toolbox (when editing a Tex1 manually, it automatically edits any Tex2 in the same folder with the same filename). Alternatively, they can be disabled with Auto MipMap removal (has the side effect of making the textures take a moment to load correctly).
  • .Tex.sbfres files contain both textures and mipmaps (Switch). Unlike on Wii U, mipmaps don't cause any problems here.


BFEVFL is used for in-game events (which includes things like talking to people and also full-blown cutscenes).

Use EventEditor to edit event flowcharts.


ResourceSizeTable.product.rsizetable (known as the RSTB) contains sizes for almost every file in the game (calculated from the non-Yaz0-compressed file sizes). If you edit a file to make its filesize bigger, you'll need to edit this file to prevent errors. The recommended tool for manipulating the RSTB is rstb. Wild Bits also provides a GUI frontend for rstb.


SARC archives contain collections of other files and folders, like .zip folders.

Use sarc to create or modify archives. Wild Bits also provides a GUI frontend for sarc.

Map units

Map units can be edited directly by modifying the map unit BYMLs or with a graphical tool such as Ice-Spear.

For the first method, refer to #BYML.

For the second method, follow the instructions in the official repo for Ice-Spear builds.


msbt files contain game texts. Convert them to an editable YAML format (and back) with msyt or (built on top of msyt) msyt-tools. Wild Bits also provides a GUI frontend for msbt.

Reverse engineering

To reverse engineer the game executable, it is strongly recommended to have a copy of IDA Pro 7.0+ because the main executable is fairly large and IDA is as of September 2018 the only serious option for analysing such binaries. It is also the only tool with a usable decompiler for AArch64 (Switch).

To get a copy of an IDC for Switch 1.5.0, ping leoetlino.