Beginning as a relatively unassuming side mode in Call of Duty: World At War, the franchise's famous zombies mode would soon blossom into an important third pillar of gameplay, helping to boost sales of some of Treyarch's greatest games and eventually spilling over into works developed by Sledgehammer Games and Infinity Ward.
Though it was more or less devoid of a cohesive narrative when it first started, CoD's massive zombies campaign and interconnected web of obfuscated stories and far-flung plot threads. Of course, revealing these stories usually requires solving some Easter eggs, some of which can be incredibly difficult to sort out.
Floating Ball Step (Moon)
Moon is one of the most divisive Treyarch-developed zombies maps of all time; some love it for its creative setting and unique mechanics, while others detest it for its disjointed nature and obnoxious decompressing pathways. However, most zombies players agree that it features one of the greatest Easter eggs in Call of Duty Black Ops history.
Yet, epic as it is, the egg is hindered by one fairly early step. After waiting for Tunnel 6 to decompress, players will be forced to escort a floating ball across the map to the MPD. While not overly-difficult, keeping track of the thing while fending off the undead hordes can be difficult, and it also requires that at least one player have the wave gun, requiring an untold number of box spins.
G-Strike Step (Origins)
Much like Moon, Call of Duty Black Ops II's Origins features a massive Easter egg that sent shockwaves through the zombies community and changed the course of the mode forever. That said, it wasn't all that easy to accomplish—particularly for solo players.
To start with, players had to go to the trouble of creating the G-Strike grenades, which was easier said than done. Then, they had to throw them out of bounds on a particular spot near Stamin-up and then immediately press a button inside one of the giant robots. While relatively easy in co-op, this required some serious patience and preseason for those going it alone.
Mahjong Tiles Step (Die Rise)
The lukewarm follow-up to the universally-despised Black Ops II launch map Tranzit, Die Rise was one of three maps to feature two Easter eggs. One favored the now zombie-ruler Richtofen, while the other favored Group 935 scientist Ludvig Maxis.
Maxis' Easter egg was far and away the more difficult of the two, requiring players to use unconventional weaponry and demanding quite a bit of patience. The final step consisted of finding and decoding the meanings behind four Mahjong titles which corresponded to support beams on a radio tower in the middle of the map. Despite being a shorter Easter egg than many in terms of total steps, it was a huge headache for anyone daring enough to attempt it.
Payphone Step (Shaolin Shuffle)
The Infinity Ward-developed Infinite Warfare doesn't get much love from Call of Duty fans, and, despite being an overall lackluster entry in the long-running franchise, the zombies mode at least attempted to introduce a few new concepts and ideas. Plus, it boasted some particularly novel and lengthy Easter eggs.
One of the most arduous in series history, however, has to be Shaolin Shuffle's. Nearly every step feels convoluted and overly-devious, but none could be worse than the section that requires players to decode actual Morse code messages emitted from a payphone. This wasn't the only time Morse code was appeared in a zombies Easter egg, but it was certainly one of the most annoying.
Dials Step (Voyage Of Despair)
Most of the Easter eggs featured in Call of Duty Black Ops 4's zombies mode are strictly for the pros, as they're overwhelmingly difficult and often include some insanely tedious, arbitrary steps. Voyage of Despair was particularly guilty of that, forcing players through an obnoxious gauntlet of symbiology and astronomy.
One of the first steps requires players to find several symbols and clocks throughout the map which then correspond to various sets of dials found on the bridge and the rear of the ship. It's incredibly tedious and requires a very reliable memory—it's something that would be tough to solve without a horde of zombies on your tail.
Gramophone Step (The Final Reich)
While it wasn't particularly well-received by the zombies community, WWII zombies attempted to capitalize on the nostalgia for the World At War's zombies mode while also doubling down on the horror elements present in the initial version of Treyarch's horde mode. Though successful in some ways, many believed WWII zombies to be overly-derivative.
Case in point, the Easter eggs featured in the mode were complicated merely for the sake of it. Among many infamous moments, one truly obscure step required players to kill an unknown number of a specific kind of zombie near a gramophone in The Final Reich. Players would then have to listen for a series of taps which would correspond to numbers on a machine in the salt mines. It was troublesome, to say the least.
Sophia Challenges (Gorod Krovi)
Often recognized as the most difficult Easter egg to complete in Black Ops III, Gorod Krovi's main mission requires players to craft several items and have a flawless knowledge of the spawn locations of dozens of items, and Sophia's trophy challenges, in particular, will test the mettle of any zombies veteran.
Though some aren't as difficult as others, doing six challenges back-to-back can be tiresome. These challenges require players to escort drones, locate orbs, or defuse bombs within a limited amount of time.
Meistermeuchler Boss Fight (The Darkest Shore)
Returning to Call of Duty WWII, the first zombies DLC map, The Darkest Shore, took things up a notch when compared to The Final Reich and required players to complete strenuous steps like holding out against hordes of zombies in a room full of traps to playing a literal game of Battleship with an insipidly imprecise canon.
This all culminates in a multi-part boss fight against the Mesitermeuchler, a much more durable variant of the already-intimidating Meuchler. Players will have a powerful too at their disposal in the form of the Hilt of Barbarosa, but this boss fight will prove rage-inducing for all but the most seasoned players.
Cylinder Step (Gorod Krovi)
Unquestionably one of the most infamous Easter egg steps in Call of Duty zombies history, many Black Ops III players attempting to solve the Gorod Krovi egg were foiled by this nearly-nonsensical step. After incubating a dragon's egg and powering up a generator, players must find a set of valves and input a series of codes based on the lights on the cylinder machines and the locations of the cylinder itself.
Deciphering these codes unaided is nearly impossible, and players are almost required to visit a fan-made website to sort this step out. Most will agree that Treyarch went a little too far with this particular part of the Gorod Krovi puzzle.
Spectral Bird Step (Blood of the Dead)
When it comes to tough-as-nails Easter eggs, most zombies fans would argue that Black Ops 4's Blood of the Dead is deserving of the title of most difficult. A convoluted mess of extremely vague and player-unfriendly steps, this is the be-all-end-all of zombies trials.
By far the most infamous step in this already horrible sequence is the one that has players searching the entirety of the map for a spectral bird which can only be seen with the spectral shield. Often hidden in some truly devious areas and with something like forty total spawn locations, this ghostly avian is an outright pest. Plus, it has to be found a total of four sperate times!