I think i'm going to go for Twine as an engine but you cn only really make text-based games. I can add background /text colour changes but not much else. What do I do?
Hmmm well my suggestion is work with what you have and just run with it. Twine is good for very specific games with a very specific aesthetic so take a pen and a piece of paper and write the most compelling story about parallel worlds.
Just remember that one of the category is graphic so maybe explain away some in-world backstory why your character is an ' i '