Thank you for the great comment :)
I wanted to implement a proper boss fight after the portal! Like a giant(er) slime. But sadly I wasn't able to implement it anymore in the time.
I had a hard time differentiating layer masks and layer collisions, but I think I get them through in the end... I think...
Oh thank you for that note on the music. I did not use headphones, I kind of just added in the music. I didn't know any of those Audio tricks so thank you! Certainly something for me to keep in mind moving forward.