Nice work, the sprite design is really good, I like the bold colors and details, it's very easy to understand the rewards and enemies in the game. I like the variety in layouts in each level. The difficulty level seems pretty similar throughout the game, so I would try to increase the difficulty as the player progresses. It looks like you can't restart the game once you make it to the end, I'm not sure if there's an error in the game template, but it should be able to restart.