Getting Started

Behavior Graph Studio is a standalone desktop editor. It runs outside Fallout 4, on your PC. You use it to open and edit the game's Havok behaviour files, then load the result in-game the same way you would any other mod.

Requirements

• Windows 64-bit or Linux x64 (both are supported natively, the same build works on either).
• No separate installation of Havok Content Tools, and no Java for the majority of edits (changing values, renaming things, growing arrays). Java is only needed for structural edits that add or remove objects, and the tool tells you if it can't find a Java runtime when that matters.

Download and run

1. Download the latest release from Nexus Mods or grab a build from GitHub.
2. Extract it anywhere on disk. It's a self-contained build, not something you install into your Fallout 4 folder.
3. Run BehaviourGraphStudio.exe (Windows) or the Linux binary. No installer, no setup wizard.

Opening a file

You have two ways to open a behaviour:

• From disk: point it at any .hkx behaviour, character, or project file you already have extracted (for example, one from a mod you're building).
• From archive: use "From archive..." to read a file straight out of a Bethesda .ba2 without unpacking it yourself. Every vanilla behaviour ships inside Fallout4 - Animations.ba2. Type a few words like "dogmeat behavior" to filter its index down to what you want. A file opened this way is a read-only copy in a temporary folder, so Save is disabled, and the window tells you where the copy landed if you want to move it somewhere of your own to actually edit it.

Once a file is open, head to Tree & Graph View to see what's inside it.