One Small Hack for a Man... - In Moon, hack something.
Self-explanatory. Use the hacker and hack something.


Fully Armed and Operational - In Moon, acquire 3 Pack-a-Punched weapons at the same time.
Self-explanatory. Have 3 Pack-a-Punched weapons at the same time.

One Giant Leap - In Moon, become trapped in the Receiving Area and free yourself through resurection in co-op.
To complete this, the player must be in a Co-op game, and let Excavator Pi and Omicron breach Tunnels 6 and 11, but one player must be on the other side before the second of the two comes down. This player mustn't have the Hacker equipped. They must then go down and the other player(s) must then survive the round and let the dead players respawn, they will respawn on the other side of the Excavators and earn the Achievement/Trophy.
(via Nazi Zombies Wiki)

Ground Control - In Moon, prevent each excavator from breaching the base in one game.
When the Griffin Base PA system announces that an excavator is moving, run to the Receiving Area and use the hacker on the appropriate flashing console.


Perks in Spaaaaace - In Moon, purchase every Perk in one game.
I completed this by buying Quick Revive and 3 other perks, going down, and buying the other 4 perks after getting revived.


Cryogenic Slumber Party - In Moon, complete Richtofen's grand scheme.
Open the MPD with Samantha inside. (Can be done in solo)


Big Bang Theory - In Moon, gain sweet, sweet, revenge.
Blow up the Earth. (Has to be done in co-op or in solo with mods)

Like any other music EE in the Black Ops games, you have to find 3 teddy bears around the map and press your use key on them. After all 3 are pressed a song will play.

The song Coming Home written by Kevin Sherwood and sung by Elena Siegman is the song that plays.

The locations of the bears are as follows:

1. On a pile of crates below the Receiving Area next to the jump pad.
   
   
2. In the airlock between Tunnel 6 and the Power Room, behind a small metal grate.
   
   
3. Behind the wall in Tunnel 11, in the same room as Stamin-Up. The helmet makes it more noticable.
   

Once again the first step is to turn on the power. Power can be found by going through either tunnel but almost everyone will go through Tunnel 6 because a later steps requires you to go there. The power switch can be found across from the MPD in the main cave.

The next step will require you to play "Samantha Says". The 4 consoles needed to play on can be found outside the Receiving Area near the Tunnel 6 door. You will to play until all 4 screens repeatedly flash green and a sound will play: "Integrity check complete. Main systems online. Arming internal routine check."

You will now need to go to the lab. In the lab in one of 4 spots is the Hacker. Grab the hacker, then go to the second floor of the lab. You will need to hack one of the 4 buttons on the wall. After that there's going to be 4 panels around the lab that have a green light glowing above them. You will need to hack all 4 of this panels. Then make your way to the second floor of the lab and press your use key on all 4 of the lit up panels. This can be done in solo or co-op.



There is a time limit to this step. Each object to hack takes roughly 5-10 seconds to hack. If more than 60 seconds has passed, you will have to restart.

This next step is going to require some patience and luck. You're going to need Excavator Pi to dig into Tunnel 6 and decompress it. After the tunnel is decompressed, hack it's terminal to move the excavator away. Go back to Tunnel 6 and knife the Vril Sphere. It will bounce around the map you will have to follow it. At one point it will fly outside and go on top of a satellite dish above the Receiving Area. You will need the Zap Gun Dual Wield in it's combined form to shoot it off. Another point in Tunnel 11, it will get stuck in the ceiling and you will have to shoot it again. Eventually it will go into the pedestal in front of the MPD and a tube will rise from one of the corners.

When the tube from the floor of the MPD rises, you will need to kill 25 zombies near it to fill it. After it is filled you will need to pull the switch on the side of the MPD. Doing this will grant you the achievement Cryogenic Slumber Party.


(You can download a mod to where you can complete the Easter Egg solo as Richtofen)

You will now need to head back to Area 51 for some panels. To the right of the perk machine that spawns in, is a pair of hexagonal panels on a top shelf in the distance. First throw a grenade at the panels so they fall on the floor. It is better to cook the grenade so it doesn't roll away from the panels. After the panels fall on the floor, throw a Gersh Device at the panels so they teleport onto the teleporter. Then head back to the Receiving Area at Griffin Base. Another player will then need to throw a Quantum Entanglement Device at the panels on the floor. They will teleport to a computer terminal in the corner of the room.



Now to head back over to the lab. In the lab is a silver tube you will need to grab. Most of the time it can be found on the top of the steps to the third floor. Other times it can appear the corner of the other floors. Grab the silver tube and bring it to the terminal.



Next, the player as Richtofen will have to insert the Vril Device with the Focusing Stone into the machine. Richtofen will say a voice line and the computer screen will flash red. The player as Richtofen will then have to repeatedly press the use key until the computer screen turns green.

After the screen turns green, grab the Supercharged Vril Device as Richtofen and head back to the MPD. Walking up to the MPD will cause 4 tubes to rise from the corners of the base. Fill up these 4 tubes then place the Supercharged Vril Device into its slot. This will cause Richtofen and Samantha to swap bodies, and Richtofen has taken over the zombies. Players will now have all 8 perks.

Toss another QED at the Vril Sphere. This will make it teleport outside to Samantha Says. You will then have to play Samantha Says 3 times. This means do the sequence until the screens all flash green repeatedly, 3 times. This will cause the 3 rockets to rise from the canyon outside the station.

For the final step, throw one last Gersh Device at the Vril Sphere on the ground and watch the Earth blow up. Now go play Black Ops II and end Richtofen's rule over the zombies.