I've been busy for some time, so I've had less time to work on this. However, yesterday I mustered up the strength to finish the actual shooting aspect. Previously the shooting was delayed, so I worked to fix that and make it more like Megaman. For this character, it's a maximum of two shots on screen at once.
So, as you might see there, I added little cat NPCs to shoot and kill. The cat is called Tango and it's a character from the Megaman 5 gameboy game. The cat takes 4 hits for you to kill and simply respawns after some time for now.
Give it a try and tell me if it matches up with Megaman! Or if you find any bugs.
Megaman Filess.zip
Please add WASD, its so awkward to have to cross my hands to test this. These games were made on consoles, and directional movement was controlled with your left hand on the direction pad. It makes no sense to have it on the right hand side.