Arrow keys to move. E to toggle whether it moves or not. Use the sliders to change the box's size and position. The box is meant to push the SOUL back if it shrinks. While I was coding this, I felt making this was TOO easy. There's probably a bug I haven't found yet.
This project is meant to simulate the box from Undertale / Deltarune battles by Toby Fox. If used, please give credit to me and Toby Fox, as he created the original version! With this, you can set the width and height to whatever you want without having to make a new costume. Additionally, you can change the thickness and the collisions will match with it. The collisions also account for SOUL's size. Chances are, you might not be able to backpack this and plop this into your project and expect it to magically work. You might need to add other soul colours, such as blue, green, and change the code to match the physics.