Wow, you're really thrown into an epic battle, and you start with an epic weapon!
At one item that said spacebar, I hit that a bunch and it looked like you had achievements built in? I think I got one for jumping 10 times. But after the credits window came up on screen, I got stuck behind it and then my gun would only shoot to the right. Even though the action is so heavy it was pretty hard to focus on 'finding robot parts' (not sure I saw any), the intensity of the fighting was actually pretty fun and juicy. I think the location of the gun barrel while swinging it around made it feel a little disconnected from your character.
Head first into some confusing fun.