you need to complete the game first then go on to spec ops and there it is dead ops.
you unlock "five" the pentagon level for zombies. you also unlock the dead ops zombie arcade game.
"DOA" unlock Dead Ops. "ZORK" Unlocks an achievement. "3ARC UNLOCK" unlocks a Zombie map
you hack the server with the 3ARC UNLOCK cheat, figure out where the server is in another question!
get up from the chair in the menu, go to the computer and type in DOA
DOA -unlocks Dead Ops Arcade. 3arc unlock -unlocks everything 3(trey)arc! =.=
You need to unlock the weapons.
an achievement
yes, there is Dead Ops Arcade. enter the code 3arc unlock to unlock this mode, and/or five.
Ranking up...
its one of the first things u unlock
You use the computer to input codes like: DOA-unlock Dead Ops Arcade 3ARC INTEL-unlock all Intel for viewing 3ARC UNLOCK-unlock all zombie maps
from black ops website