Just... wow. Absurdly good game. I can't stress enough how good this is. I'm gonna leave some suggestions, but only because I know even excellent games need feedback.
First, I would prefer that as the game goes on the larger items scale better than the smaller ones, thus encouraging me to ditch small easy to carry rings and try to get tricky making crazy shapes work because square for square they are better. I ended up on lv 17 wanting to play more but I had only 1, 2, and 3 square objects and the whole stress of the game was gone. Second, I would speed up the clock of the entire game every level thus making it even more stressful as you go, trying to swap objects in less and less time and in more and more complicated shapes trying to juggle actually making progress on your stats while also not accidentally deleting things and losing. Lastly, I would show whatever numbers the combat is generating as a distraction and to make the slow parts when you don't need input for a while more fun, and to make the individual stats and monster types more useful.
Bravo.