Custom player collision shapes

Hello!
I am seeking to create a system that allows me to use a capsule/box as collision rather than the root part or limbs.
One example I have of what I am attempting to achieve originates from Die of Death.

The picture above shows how the system appears in-game. The red shape located near/in the torso acts as collision for the player.

I have tried to make a collision instance that is welded to the root of the character, but it is very unreliable and janky. I feel that there is a better solution than mine out there so I am now searching for help here!

Any help is greatly appreciated.

I have tried to make a collision instance that is welded to the root of the character, but it is very unreliable and janky. I feel that there is a better solution than mine out there so I am now searching for help here!

Probably add this, so instead of the server handling the Hitbox, is the player who will handle it
Part:SetNetworkOwner(Player)