I assume the game ends after I defeated the frog as I can't come back further away than the previous room?
The game is cool. It could work as is on an NES, the songs are nice and the game has a nice, consistent and distinctive look, I specially like the look of the frog and swallows. The game feels good to control and the boss fight is a good one, 100% NES-like and with an appropriate difficulty for the jam.
Thanks for sharing!