Download the R15IK Blender archive and open it, you will see a Roblox Rig and a bunch of others things. Must be something like this Now, let's see how to animate with the Rig.

In Blender, a popular and free software for 3D modeling and animation, you can rig your character with bones and constraints, which are tools that define the structure and behavior of your skeleton.

This project creates a character animation rig using a script that automatically applies Inverse Kinematic constraints on specified bones of a human Metarig from Blender's Rigify Add-On, effectively ...