Actor packs are Yaz0-compressed SARC archives that contain parameter files defining the behaviour of a specific actor, as well as any physics files that actor requires. Their file extension is bactorpack (or sbactorpack when compressed).
Actor packs can contain these directories:
Its canonical resource path is "Actor".
The Actor directory contains files defining the actor objects that populate the game world (e.g. enemies, buildings, NPCs). It also includes configuration files for the actor and AI system.
Physics contains configuration files and Havok binary packfiles for the Havok physics engine.