The Binding of Isaac Afterbirth+ had an instruction booklet for those that picked up a physical copy. Looks like Cave Story+ is going to do the same. The booklet with Isaac spoofed the style of the instruction booklet for the original Legend of Zelda. Is this Cave Story+ manual going to spoof something as well? Going off of just cover art, Metroid on the NES had a gray booklet as well. The two games certainly have similar styles!