This put a huge smile on my face. I imagined most people who booted this up were confused and immediately closed it, but to hear you've gotten that far with your partner makes me really happy. The fourth one is in the deathrun area. If you look at the right side, there's an invisible wall along the bottom that you can enter. Here's a screenshot where you can see a lighter yellow line along the right wall where it is. I admit this is a very sneaky place to hide something and I probably should have made it a bit easier haha. Thanks again for the very nice comment and I hope you two can see the ending!