Wow, really a great game, good job!
The pixel art was amazing and I wished the sprites weren't too small in the screen to better appreciate them. The music was good at the first minutes but became very annoying if listen too much.
Very nice use of the theme and the limitation. All in the game remember cats: the black cats as enemy, the water inflicting damage, the cats been distracted by the ducks and many others aspects.
I was a little scared with the amount of rules right on the start screen but the game turned out to be very intuitive.
Good entry! Congrats!