Avatar Joints Upgrade (Roblox Beta Features)
to find this game you need roblox studio installed, first go on devforum and search "Avatar Joints Upgrade" click the first option, Second step you keep scrolling down until you see an link to the game Physically Simulated Characters Demo and click the 3 dots on the game then you press "edit in roblox studio" have fun! ignore the jarate on the thumbnail tho