Right. I'm new here and this is my first post, and sorry if this hasn't been mentchoned before, but on shi no numa, The room you start in. if you go all the way to the end of the room and look at the piles of boxes it has the number 115. and also through shi no numa you find the meteorite, in which i think is the doctors quarters , outside of the fence is a largemeteor, and you're character says a line. But the meteor has an element running through it. The same energy from the wunderwaffe. This is what the number 115 means, and on kino der toten (cinema of the dead) you can find three pieces of that meteor. ones located underneath the stairs in which you start, and one is located in the dressing room by some maniquins. The third however is in the room above the alley on a shelf. you can ollect these rocks by pressing square on ps3 and x on xbox. but once you pick up the meteorites, it plays a song called 115.
I am also On PS3 if you want to do zombies together. Thank you :)