Update 05/10/2025: Unity has announced builds created with version 2017 and later are vulnerable to a malicious exploit. This is wide spread and affects the majority of games released and built in recent years.

I've temporarily pulled the download for this project to protect players until I've been able to built a new version, safe from this exploit. Until then, feel free to check out the devlog!

Sorry for the inconvenience, and thank you for understanding!

RE2 Mr. X - Behaviour Tree

A technical exploration and recreation of the 'Mr. X' AI system from Resident Evil 2 Remake (2019) using my own implementation of a Behaviour Tree (BT) system. This project serves as my first dive into video game AI by creating a BT from the ground up.

Mr. X is a video game AI that hunts the player through the level, stalking the halls and searching rooms. I've attempted to reproduce that behaviour to learn how to create a basic BT system.

Check out the devlog!

Features

• Custom Behaviour Tree built from the ground up with behaviour mimicking RE2’s Mr. X within Unity.
• Various Node types such as Composite, Action, Decorator and more to create patrol, search, chase and attack behaviours.
• Room System with AI Door handling for Room-to-Room navigation.
• Door Handling solution enabling the AI to interact with and navigate through Doors effectively.
• Object-Oriented architecture using inheritance to define type-based and abstract logic.
• Room real-time lighting optimisation techniques.
• Fully playable vertical slice with traditional gameplay systems to test AI implementation in an in-game setting.

Assets

• Mr. X Model - Dollymolly And Red Menace (not possible without!)

Note: Capcom reserves all rights to the 'Mr. X' character. I do not claim to own this character, only use his likeness in an AI development study out of my love for the franchise.