Here is the full easter egg guide for Operation Loucher!

Step 1: Turn on the power and fill up all of the soul machines.
Step 2: Once you have filled all three soul machines, pick up the fuse that spawns on the teleporter and place it in the console directly opposite.
Step 3: Acquire a Wunderwaffe from the box and PackAPunch it.
Step 4: Shoot the three origins generators with the upgraded Wunderwaffe at the base of their control panels to overload them.
Step 5: Collect and place the second fuse (found in the control room again).
Step 6: Keep killing zombies with any type of upgraded weapon to spawn the third fuse at a random corpse.
Step 7: Place the third (final) fuse into the console.
Step 8: Use your upgraded Wunderwaffe to overload the teleporter by standing and shooting down at it.
Step 9: Accept the prompt to end the game and enjoy Madgaz's amazing teaser for his next map.

If you need a video to see exactly what to do you can find my full Easter Egg guide at this link:
https://www.youtube.com/watch?v=oet8b9PA1Hg

Happy slaying!