Object that can rotate freely around a center

Have a nice day. I'm trying to make a game like Hammer Fight, but I have no idea how to make a hammer. When the vehicle moves, the hammer should be able to rotate or swing freely around the vehicle by accelerating with the effect of its own weight. There must be a pole or rope connecting the hammer to the vehicle. This rod or rope should also be able to realistically spin and slam with the hammer. I'm trying to make my game in 2D, but if I can't do it in 2D, I can continue to develop it in 3D.

I'm open to any ideas. Some places may be weird because I wrote this message with google translate. Thanks in advance.