TheEndlessAbyss
Please choose troll hunters it is a very good world it has magic and science there is a lot of material that you can use you could use enzyme two other series that are related and the best thing is that canonically it is possible also there are too many stories of avatar the last airbender and I admit I'm also interested in adventure time but it's very complicated to put together an original plot with this one and let's not talk about whether you want to do it correctly chronologically.