Great Game! Congratz!
I got a few feedbacks for improvement, but overall it's a hit!
Movement: perfectly done, with high quality to the perspective! I just think the stage border was a little unclear on the first level and could mislead the player to avoid obstacles to wrong side when the almost full screen obstacles apear. Really good care for the movement progression, teaching the up and down move after perfecting the side movement first.
Shooting: It wasn't very clear the effect of the missile instead of the normal laser beam. I think there was a big rock that required a missile shot in the second stage, but I'm not sure if it was just a normal rock in my face because of the perspective. For the final boss I got a little tired of clicking fire. Maybe in the end you could turn on auto-fire, but I'm glad you used both keydown and keyup to shot, otherwise it would really be painful.
Text: It was a bit janky because of the constant changing size and characters. Maybe using a darker color but keeping the same size would fix this issue. It is quite distracting
Sound: Great sound! But made me question how GB like it was.
Overall a really fun game to play! You all did a great job!