There's a surprising lack of laughing dogs. :)
I love the pixel art, but the gameplay is too simple to be enjoyable.
I probably can't avoid comparing this to Duck Hunt.
https://youtu.be/x-daxzVxrQI
Notice that in that game, the ducks come in waves, you have to react quickly and their fly trajectory is unpredictable. It keeps you on your toes.
Here, the ducks follow completely predictable straight lines, there's a lot of them and you can take as much time as you need. I don't even need to move the crosshair and just wait for the ducks to come in the line of fire. And it is a full line, so you're almost guaranteed to hit something as your bullet moves across the screen.
I wouldn't say it's boring, but certainly very casual.
Also, there's no animation for shooting the ducks (they just blink out of existence), the crosshair should be pixel art, too (since everything else is) and the score panel (and the score count itself) isn't aligned properly (outside of full-screen).