Fun puzzle, clear interface, through I wish I could use keys instead of clicking.
But I'm giving up now: I'm stuck on lv14, can't kill the top orc. I think you have to kill him standing in the corner, just as he turns, but I tried several times and different timings and haven't managed. I could get closer using water, but that water is needed elsewhere to get the key. Is it my browser? Or is there a 2nd bottle of water hidden somewhere?