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Just like last time, there isn't really anything worth going in depth about. And once again if you want, you can change into your human form and bypass most of the enemies.

[edit] Boss: Rayfly

This boss isn't too hard. His only attack is dropping a stack of three blocks, which will shoot bullets at you. In order damage him, wait until he is right over the blocks he's laid down, then shoot whichever block is red until it explodes, making the other blocks fly up and hit him. Just do that several times and you'll kill him.