Call of Duty Zombies has come a very long way from being a surprise mini-game in Call of Duty: World at War. With over a dozen maps across multiple iterations of Call of Duty, the game has taken on a life of its own. An extremely complex and often hidden storyline has only added to the mystique of the fan-favorite game mode and allowed development to push the envelope while still allowing the mode to feel like the original.

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With Easter eggs going as far back as Call of Duty: World at War, many fans are eager to play the game just to solve the hidden puzzles that come with it. Some of these quests don't require much from hitting a few buttons, whereas others are complicated multi-step puzzles with truly awesome payoffs that reward players' patience and skills at defeating the undead.

Moon (Hardest)

The Moon side quest in Call of Duty Zombie

One of the things that make some of the Easter eggs so much more difficult than others is the number of players needed to complete the quest. Unlike other iterations, which can be done solo, the Moon Easter egg requires full cooperation between all four players, a feat which is difficult in itself.

Beyond that, it requires hours of playtime and skilled players must get lucky with the mystery box, and complete a dozen complicated steps. However, some may find it worth it for the achievement and bragging rights that come with its completion.

Teddy Bear Music (Easiest)

A teddy bear inside a barrel

Featured in multiple zombies maps, but best known for its use in the Zombies mode in Call of Duty: Black Ops 1, the Teddy Bear Easter Egg is one of the most well-known and easiest Easter eggs to date.

Players must simply locate and activate three teddy bears hidden throughout the map. Upon completion, a song will play while you fight off the hordes of the undead. Each map has a specific song to go with the Easter egg, with Avenged Sevenfold even creating a song specifically for the Easter egg in Call of the Dead.

Shangri-La (Hardest)

Shangri-La as depicted in Call-of-Duty-Zombies

There were some Easter eggs in the DLC zombie maps added to Call of Duty: World at War, but they really took on a life of their own in Black Ops 1. With the introduction of the map Shangri-la, it's possible they pushed the envelope a little too far.

Another Easter egg that requires hours of gameplay and the cooperation of four players, Shangri-la is one of the hardest to complete. Aside from the difficulty of the steps themselves, the map is very close quarters, making normal gameplay difficult. Add in a complicated quest and many find it impossible.

Call Of The Dead (Easiest)

A zombie roars as a character approaches from behind to shoot it

A rare multi-step Easter egg that can be completed in solo mode, the Call of the Dead Easter egg is far easier than some of the others over the years. The quest does become more difficult when you add three more players, but even then, it's still quite doable even for lower-skilled players.

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Spinning dials, retrieving fuses, and carefully placed grenades seem like child's play compared to other maps. The reward is well worth it too, with players that complete it getting their hands on the powerful Wunderwaffe.

Origins (Hardest)

The player stabs a zombie astronaut

Another map that is plenty difficult on its own, whether your playing solo or with friends. also has one of the most difficult Easter eggs in the franchise. Again, requiring a very long time to complete, as well as all four players being involved, few have fully completed this Easter egg.

Requiring players to create four staffs that are admittedly fun to use, the Easter egg simply takes forever and there are a ton of ways for it to go wrong. Completion is immensely satisfying though, as it presents a cut scene in the middle of the game, something rarely seen in the game mode.

Der Eisandrache (Easiest)

The Eagle's Nest in Call-of-Duty-Zombies

Despite having quite a few steps, the major Easter egg for the Black Ops 2 maps, Der Eisandrache, is quite doable. Although not especially easy when compared to other Easter eggs, this one is arguably the most fun and rewarding.

This is because players gain access to powerful bows before the Easter egg is even fully completed, meaning that even doing just half the Easter egg is often worth the time and effort.

Shadows Of Evil (Hardest)

The Black Lace Burlesque in Call-of-Duty-Zombies

Love it or hate it, Shadows of Evil is one of the most unique zombies maps ever created. With a ton of new elements, new characters, and a unique setting, there is a lot to take in. With so many new things to think about, seasoned players will likely struggle quite a bit to complete this Easter egg.

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Needing lots of coordination between players, and a keen eye as you look for important symbols from a moving tram, this Easter egg can quickly become overwhelming to those unfamiliar with the map.

Ascension (Easiest)

An abandoned cosmodrome in Call-of-Duty-Zombies

It may take a ton of steps and some special equipment, but the Ascension Easter egg is surprisingly easy, assuming the player knows the proper steps, as the map has lots of open spaces and is relatively small compared to some of the more recent maps.

Even though it requires some coordination, the steps requiring all four players are often as simple as pressing a button, making it easy in comparison.

Gorod Krovi (Hardest)

A fire-breathing dragon in Call-of-Duty-Zombies

An already difficult Easter egg made significantly harder by a difficult and often confusing map, the Gorod Krovi Easter egg can be intensely frustrating, as fire-breathing dragons, giant robots, and tight spaces can make staying alive plenty hard.

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Still, the cut scene that players unlock upon completion just might make all the trouble worth it, though it may prove confusing to those not well versed in the Zombie storyline.

Zetsubo No Shima (Easiest)

An abandoned factory in Call-of-Duty-Zombies

With plenty of steps and lots to memorize, Zetsubo No Shima can seem daunting, at first. However, this is another Easter egg that is rewarding even without fully completing it.

Allowing players to create powerful weapons and fight unique creatures, even average zombie players shouldn't have to spend too many hours trying to complete this one. With multiple boss fights, the main Easter egg will allow players to fully appreciate an often underrated map.

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