Okay, this one is often made much worse than it seems. This achievement is best done on KINO DER TOTEN (as is are all of my tips) The best thing to do is to get TWO AND ONLY TWO people to do this, as when u get more than this everyone will inevitably start yelling about who gets shot first. The fist step to this is to designate what my friends and I lovingly call a "Door B*tch" this will be the person who does nothing but open doors for the other person. As both people get an achievement for 1 successful attempt this is easy to do. (Both people get 2 'nades after each round and 2 claymores every round as well, these stay in place during several rounds as well, I highly recommend both of you buy claymore for points and crowd control.)
1*++Do not buy guns++Spend the first round shooting each zombie 4 times in the chest followed by a well placed very satisfying shank. An important part of this is to shoot the zombie and leave him alone LET THEM IN this round, when they enter kill 'em and rebuild. Both of you watch 2 windows.
2* Round 2: This time shank them as soon as you can don't let them in as you can become overrun, do nothing but knife, You'll need to save the ammo for round three...hopefully you'll have gotten a max ammo by now. I normally did.
3* Round 3: This time the Fuhrer's forces are coming full tilt, do everything you can, use grenades! they can slow, kill, and damage and are worth their weight in gold. Shoot, stab and blow your way through them. remember to knife if u get an 'insta-kill" I've combined this with a "double-points" for massive points. At the end of this round leading into round four board up all the windows.
4* Round 4 in this round you will first enter the room in the lower left side off the starting or "Tele-pad" room. This room contains an MPL check for the box if it is not here move up to the to right room containing the PM-63 if the box is not in this room open the room containing the MP40. if not the MP5K room, if not the back-stage. Now many will ask "why not open the AK-74u alley and stairway entrances as well?" Well these are easy clogging points and NEVER OPEN THE STAIRCASE as you will be making a stand in the backstage area. If you have opened all the rooms without the ones I never said 2 open, and not found the box, start over. Now you need to have found the box before round 6-8 as the enemies can take some punishment after awhile.
5* Rounds 6-8 When you have found the box the first person to roll needs to be the person with the lowest ammo, or the "Door B*tch" to guard the Crossbow guy/gal. After getting a decent weapon the other player rolls until they run out of points and then you know how 2 take care of things that way.
6* Post-Crossbow (B4 round 15)
Okay don't get ****y you got the bow now the next part is crucial. Make your way to the backstage area. Get ready, the person with the best crowd-control weapon should watch the front and the other person should watch the MP5K room. Now the person with the bow does need 5k points however so keep that in mind.
7* (Post 5k) Finish your current round hopefully leaving a crawler, turn the power on. and link the Teleporters. after Pack-A-Punching to receive the fabled "The Awful Lawton" you should run around the map until you have a size-able group' in a tight group. the get away from each other and stick your pal and have him rush into them. Don't worry the arrow wont hurt ur friend and mine wasn't hurt by the zombies. Blow these bastards to hell.
**If you cant get it lemme know and I'll be able to help yah!**
GOOD LUCK