Great work on your first game! Definitely agree with ramping up the difficulty would help a lot and having a death screen/pause between runs would be appreciated! I also found the controls to be a little finicky as the cat got stuck moving downwards for me. I think you could really grow this idea it a really cool bullet hell style game! Appreciated the way you could use the water and the house to avoid the slimes! I also think not starting by the water would help with understanding the fear of water and having other obstacles for the slimes to move around would help with the dodging and feeling like I should move around the map. Also making the fear of water more of an obvious change associated with the red screen since not all bodies of water causes it I think would be a great touch! Congrats on your first game I hope you make more :D