It's too bad that I took out the Wunderwaffe. There's a chance you can get the Ray Gun, though. It still gives Splash Damage. BUT. Take it to the Pack-A-Punch Machine, and it transforms.
It's longer, and lacks Splash Damage.
Oh, and the upgraded guns get new names.
PPSh-41: The Reaper
Ray Gun: Peter's Lil' Ray Gun
So, pumped up for Der Riese? ZE VAFFENFABRIK der RIESE?!