Very creative gameplay loop--really enjoyed the gameplay mechanic.
The visuals are simple but effective--excellent for a game with only 3 hours development time! Also loved the particle effects!(Ive been experimenting with particle effects a bit now and it is a game changer--literally!)
A small suggestion could be an arrow that extends on charging the box--showing the power of the throw. However, that's all polishing stuff. The game itself is excellent.
Great job!