Hey, thanks so much for playing, that's some really kind praise! We're thinking of getting this on mobile...
So our main use of the "only one" theme was that the victory condition of the game is for there to be only one piece left on the board!
Viewing post in Einnsámr: The Lone Warrior jam comments
Ah, duh, that makes more sense. Sorry, it's late in my time zone and I've been playing dozens of these haha. I'd love if you could check out and rate my game as well, I made a puzzle game too! It's not as beautiful and polished as yours, but I hope you have fun playing it regardless :) https://itch.io/jam/gmtk-2019/rate/460707