Hm since you cannot really post images in Showcase threads and my old projects thread is rather dead, I will make a Superku development post here for now:
I had this idea for a level where you'd activate some kind of water pump or boiler, which would then lead to rising water and you could reach heights and areas which were inaccessible before. Obviously, you'd release a bunch of piranhas as well!
The water (and to some degree the piranhas as well) posed a big problem for me, I just couldn't get it to work. It was supposed to move or rather flow around the corners of a tile based level, if possible in all directions, meaning downwards too. A simple wavy but level water line was something I was trying to avoid. One of the first (~3) tries of which I took footage, based on multiple tile based models:
