Good concept! The wrench as a physics object is a big hard to work with, especially while its spinning. The other critique I have is that the actual hitbox for the brain is really small and hard to hit. With those fixes this game would be great! Either way though good job!

Cool idea! The game was pretty satisfying once you got the hang of it. For feedback:

- I would recommend either resetting the velocity/rotation of the wrench completely when resetting. You can still make it predictable by letting the wrench land before resetting. Having it be random is frustrating and just means you reset until you get what you want as there's no real way to tell what will happen. 

-I also suggest allowing the player to manually rotate the tires as the selection of rotations feels a little limiting. I also think giving the players limited tires would also make the game feel more rewarding.

Overall, your concept has a lot of potential and I think you could definitely improve it a lot!