By now, fans of the Call of Duty series know how many easter eggs and inside jokes inevitably find their way into the game’s campaign and multiplayer stages. With Black Ops, developer Treyarch took things to a whole new level. As could be expected then, Black Ops 2 has already proven fruitful where easter eggs and hidden jokes are concerned.

We don’t know what it is about designing a Call of Duty title that allows developers to place seeming hours of time and energy into secret content that many players will walk right by, but we’re not complaining. Considering just how many countless hours are going to be spent worldwide in Black Ops 2‘s multiplayer, and the millions who will be experiencing Treyarch’s take on the future of combat, sightseeing makes more sense than ever.

This is likely just the beginning of what the hunt for more easter eggs will unearth, but it’s more than a strong start. Black Ops 2 is larger than life in more ways than one, so we predict that future map packs will contain just as many odd additions as choke points. We’ll do our best to keep the guide updated, but there’s no time like the present to start playing the game inside the game.

Nuketown 2025 Classic Arcade

Black Ops 2 Nuketown Arcade Easter Egg

Given the amount of publicity that both the Call of Duty and Guitar Hero franchises have brought to publisher Activision, there are likely few who still recall the company’s retro gaming roots. Luckily, even those who never got to experience the glory days have a chance, thanks to the Nuketown 2025 multiplayer map.

As was the case with the original Black Ops Nuketown location, the easter egg begins with shooting the heads off every mannequin found within the level. When that task is done, simply return to the video screen sporting the kill counter near the map’s center, and prepare to take a trip through time.

Activision has made PitfallKaboom H.E.R.O. (Helicopter Emergency Rescue Operation, and River Raid playable with the joystick that replaces the on-screen gun. The controls aren’t exactly as precise as we remember, but not many shooters contain a handful of 8-bit games on top of the standard gameplay.

No Zork though, so we’ll leave the judgement up to the individual player.

Thor’s Hammer

Black Ops 2 Thor's Hammer Mjolnir

The iconic hammer ‘Mjolnir’ of the Norse god of thunder might seem a bit out of place in the campaign of Black Ops 2, but the developers are clearly fans of comic book superheroes. Even if this easter egg is the easiest one to miss entirely.

When the wingsuits are used for the first time in a mission, a section of the level demands that the player eliminate a number of enemies near an elevator. When all the hostiles are cleared out, backtrack towards the ridge, and find the small ravine running alongside, near the edge of the cliff. Simply drop down, and find the somewhat hard-to-spot cave opening.

Within lies Thor’s beloved hammer, and although the cave is a little too dark to see the instrument in great detail, it is unmistakable. And no, no matter how hard the player tries it’s stuck there for good. Oh well.

Raid Basketball

Black Ops 2 Raid Basketball

This one is fairly straightforward, and may have been stumbled upon by curious multiplayer fans. On the Raid map, the large basketball court behind one of the houses is hard to miss; as for the shots themselves, well, that depends on the player.

Three basketballs are lined up along the low cement wall directly across from the hoop: simply aim the shot, and pull the trigger. The knife can also be used for those who want a bit more of a challenge, but unfortunately neither one unlocks an achievement or further easter egg.

The Zombies Are Coming

Whether this particular easter egg is merely an offhand joke or a sign of things to come is hard to tell, but given the amount of surprises that Treyarch has planted in Black Ops 2‘s multiplayer, we wouldn’t be surprised if it’s the latter.

The sticky note in question can be found in the upstairs rooms of one of the houses in the Standoff multiplayer map, bearing nothing but the cryptic warning that ‘Zombies are coming.” Could future updates to the game bring the mindless hordes into new maps and stages, starting with Standoff? Who knows?

Either way, it brings a new level of creepiness to the strangely deserted level. Not to mention makes the mindless killing of human beings at the hands of their uninfected brethren seem all the more futile.

They Call Him Skrillex

Zombies and Skrillex – need we say more? There’s no question that fans will want to unlock the song “Try It Out” by Skrillex feat. Alvin Risk. But to do so will require a playthrough of the Tranzit zombie mission. All that’s required is discovering the location of three teddy bears throughout the level, and luckily, YouTube user StealNova has already done the legwork.

Once completed, the song will be unlocked to bring even more ambiance to endless zombie-slaying. Doubt us? Have a listen:

We don’t know if electronica, techno or dubstep are the ideal musical styles we’d lay over zombie hunting, but clearly the developers felt strongly about it.

Those are the hidden secrets that have been deciphered so far, but they are by no means the only ones. The weeks and months to come will absolutely reveal even more easter eggs, and we’ll keep you updated as they see the light of day.

Call of Duty: Black Ops 2 is available now for the PS3, Xbox 360, PC, and Wii U.

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