Call of Duty: Black Ops

The hardest thing about this achievement is getting the shrink ray. After you get lucky enough, you need to shrink the following zombie types(you don't have to kill them):
Normal zombie: no explanation needed
Shrieker Zombie: wears some sort of tulban and flashes you (you can also get the Blinded By The Fright achievement if you kill it while flashed)
Napalm Zombie: Zombie with flames, you can't miss this one.
Zombie Monkey: They come when there's a power up to grab. Wait till they grab it and shrink them after. (This will also net you the Monkey See, Monkey do achievement) You can't kill the monkeys sitting at the spawn as it won't count.

They all need to be shrunk in one game and the shrink ray doesn't need to be PaP'd.

This is easier done on solo. The reason why this is easier done on solo is because the box 90% of the time spawns underground near the ak74u if it spawns near the waterfall then restart the reason for this is because there is not any good weapons near that place. When you spawn stay in the spawn shooting zombies 4 times then knifing them this gives you the maximum amount of points. (edit: on round two the zombies take two knifes to kill them) Do this for 2 rounds then buy quick revive if you feel like it. If not continue to the left side (if your facing the revive machine) open the door (750) and buy the MPL when you can. Stay here till you have about 2000 pts if you want you can continue getting points as long as you are comfortable with that. Then open the door (down by slieght of hand big round door) its best to get a crawler if you can if not don't worry about it hit the box as many times as you can. If you don't get it then start over or continue playing best to start over

When you the 31-79 JGb215 shoot a normal run of mill zombie. Then when a special zombie appears Napalm/Shrieker zombies shoot them with it kill them so you don't get distracted. Then when you get a power up (nuke, ammo ect) the zombie monkeys will swarm on the power up and pick it up shoot the monkey and there you got two achievements in the bag. If you don't want them to have to power up you can pick it up and they will swarm YOU that makes it a little easier (edit they are not overwhelming mabey two or three will spawn when a power up spawns) Normal zombie monkeys that sit on the walls DO NOT count. You need to get a power up and shoot the ones that go after the power up. This can be done in any order.

Get the weapon in the box (RARE)
Shoot the following
Shrieker Zombie - He runs around on any levl and will either go all Chuck norris on your ass or he will like spread his arms out and white looking rays will hit you. This will temporarly blind you.
Napalm Zombie - He has fire and lava like skin. He walks all the time. If you get to close you will start burning up. The AI will also say something before he comes so keep your ears wide open and listen to everything.
Normal Zombie - Pretty simple. The ones that break through the windows and the ones that started this whole Zombies expirience for everybody. Japaneese looking like zombies. Women as well.
Monkeys - You cannot shrink the monkeys they just blow up. It's pretty epic, but you only can shoot the ones that are running for your perks or away with your perks. The ones that just sit there you will not get the achievement. It still will shoot and kill them though.

UPDATE: The Napalm zombie will start to run if you leave him long enough. I was working on the Easter egg and we had him for about 10-15 minutes and he just started running.

The following worked for me in solo (mystery box started at the waterfall) ...
1) round 1, buy quick revive and just knife
2) round 2, close up one window and shoot 4/5 bullets into zombies then knife
3) round 3, close up window, shoot 5/6 bullets into zombies then knife. If no max ammo drop, buy the m14 (two shots into torso then knife) and leave a crawler
4) round 4, clear debris leading to mud-pit room and get to the other side of the bridge - buy the door and then buy the mp5k, kill the crawler
5) round 5, camp at the top of the water slide and fire 4 shots + knife to get max points, leave crawler at the end of the round
6) run to the mystery box at the waterfall and buy some guns (I got the galil and aug on 1st and 2nd attempts) then close as many windows as possible to get points before getting back to the top of the water slide, kill the crawler
7) round 6, get through the round and leave a crawler (head-shot zombies with either gun)
8) clear debris to the power room and turn on power, buy semtex and buy the bowie knife, get back to usual area and kill the crawler
9) round 7, get through the round by firing bullets and knifing, leave a crawler or a few and close up all windows
10) clear all debris all the way up to the mpl and hit the mystery box (I managed to get the shrink ray on my 4th attempt), kill the crawler
11) round 8, run around the area just below the mine cart to try and kite zombies then use the shrink ray to shrink all 4 types (normal, screamer, monkey and lava guy) - don't be afraid to spam it if you get overrun. once the zombies drop the power-ups, monkeys will try and steal them so shrink them when they are trying to run away with it.
12) Got the achievement by round 10, but if no shrink ray by round 10 - restart. If you get downed at any point, try to hold off the zombies, when you get down to the last few zombies, create a crawler and top up on the quick revive as it only costs $500.

This video shows how to get the achievement. It also shows how the zombies look so you cant miss it this time. The monkey Zombie is the most important because a lot of people don's know that you hsve to kill this one to. Have fun!

Start a solo zombie game. play untill u get the 31-79 JGb215 aka baby gun aka shrink ray out of the mystery box and make sure you have juggernog. if you have enough points go ahead and pack-a-punch it. its not needed for the achievement but it will make things easier for you. then just run around in the starting area as i did in the video and keep shooting and kicking everything that moves. you have to kill 1 zombie of every type including a monkey. the video doesnt actually show me killing all zombie types or getting the achievement but if you just follow this guide and kill everything that moves for a round or 2 you will get this achievement.