So I made a mountain.
And I thought to myself "What is the point of all these level changes?" So I thought some more and I thought perhaps different enemies could be introduced the further the game goes along. But what enemies? I thought and got "taco". I tried to draw a taco. While failing to draw a taco, I thought "perhaps a pizza." So I drew a slice of pizza. The pizza shoots nachos downwards. It will be introduced in level 5. The taco will be introduced in level 8. It won't shoot anything, but it will follow your vertical movement. So that means you need to shoot it. I don't think a taco shooting nachos would be appropriate since a taco shell is basically the same as a nacho.
One thing I need to do is make a mountain/snow theme music and then I can move to making level 5. I made the pizza code already, but I disabled it until level 5, which is not in the game yet.