LimboAI for Godot 4.x / News / May 3, 2025 / Godot LimboAI is a GDExtension for the Godot 4.x game engine that adds behaviour trees and state machine support. These make it easier to create and re-use AI logic in your game. There is also a new Godot Engine asset bundle showcased in the video, the Godot StarNova Bundle on Gumroad but be sure to use the code SN40 at checkout to save $40 off! Features of LimboAI for Godot Engine. Behavior Trees (BT): Easily create, edit, and save BehaviorTree resources in the editor. Execute BehaviorTree resources using the BTPlayer node. Create complex behaviors by combining and nesting tasks in a hierarchy. Control execution flow using composite, decorator, and condition tasks. Create custom tasks by extending core classes: BTAction, BTCondition, BTDecorator, and BTComposite. Built-in class documentation. Blackboard system: Share data seamlessly between tasks using the Blackboard. Blackboard plans: Define variables in the BehaviorTree resource and override their values in the BTPlayer node. Plan editor: Manage variables, their data types and property hints. Blackboard scopes: Prevent name conflicts and enable advanced techniques like sharing data between several agents. Blackboard parameters: Export a BB parameter, for which user can provide a value or bind it to a blackboard variable (can be used in custom tasks). Inspector support for specifying blackboard variables (custom editor for exported StringName properties ending with “_var”). Use the BTSubtree task to execute a tree from a different resource file, promoting organization and reusability. Visual Debugger: Inspect the execution of any BT in a running scene to identify and troubleshoot issues. Visualize BT in-game using BehaviorTreeView node (for custom in-game tools). Monitor tree performance with custom performance monitors. Hierarchical State Machines (HSM): Extend the LimboState class to implement state logic. LimboHSM node serves as a state machine that manages LimboState instances and transitions. LimboHSM is a state itself and can be nested within other LimboHSM instances. Event-based: Transitions are associated with events and are triggered by the state machine when the relevant event is dispatched, allowing for better decoupling of transitions from state logic. Combine state machines with behavior trees using BTState for advanced reactive AI. Delegation Option: Using the vanilla LimboState, delegate the implementation to your callback functions, making it perfect for rapid prototyping and game jams. 🛈 Note: State machine setup and initialization require code; there is no GUI editor. Tested: Behavior tree tasks and HSM are covered by unit tests. GDExtension: LimboAI can be used as extension. Custom engine builds are not necessary. Demo + Tutorial: Check out our extensive demo project, which includes an introduction to behavior trees using examples. Key Links LimboAI GitHub Repository LimboAI Asset Library Godot StarNova Bundle on Gumroad BeeHave Behaviour Tree For Godot You can learn more about the LimboAI behaviour tree/state machine AI add-on for the Godot game engine in the video below. Buying the Godot StarNova Bundle on Gumroad (use code SN40!) helps support GFS (and thanks so much if you do!)