After a slew of controversial entries in the Call of Duty zombies saga, Treyarch have returned with Black Ops Cold War, which, though not quite perfect, seems to have done a great job of satisfying CoD zombies fans both new and old. With four more seasons of content in store, we can't wait to see what's next for the legendary mode.

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The most recent survival map, Firebase Z, re-introduced the Russian Manglers boss zombies, which were first seen in Black Ops 3. With that in mind, we're interested to see what other famous boss zombies from the past could be returning to the fold in the future.

Megaton (Die Maschine)

Megaton zombie featured in Call of Duty Black Ops Cold War.

Megaton zombies were the flagship new enemies of Call of Duty: Black Ops Cold War's zombies mode when it first debuted, appearing on the lone launch map Die Maschine. Large, lumbering monsters in hazmat suits, they're made iconic by their sickly green/yellow hue and their second phase which sees them split in two.

Though not overly difficult to deal with for experienced teams, they can certainly be intimidating for new players, and, should squads fail to be adequately prepared, they can be quite a handful. They don't have the nostalgia factor of boss zombies from previous games, but that shouldn't detract from their overall appeal.

George Romero (Call of the Dead)

George Romero in Call of Duty: Black Ops

A strange entry in the Treyarch's rogue's gallery, famous horror movie director George Romero, most known for popularizing zombie movies with his seminal work Night of the Living Dead, was immortalized in the original Black Ops zombies mode. A staple feature of Call of the Dead, a zombified Romero would slowly pursue the player, flying into a rage when attacked.

With an over-abundance of health, taking Romero down was quite the feat. However, when defeated, he would reward the player with a Wunderwaffe, an all-time great zombies weapon which was first introduced in World at War's Der Riese map.

Hellhounds (Shi No Numa)

Hellhounds in Call of Duty's zombies mode.

First introduced in Shi No Numa, the third installment of World at War's zombies mode, hellhounds have been one of the few constants of the ever-changing zombies formula. Accompanied by fog and foreboding warnings in unique rounds dedicated entirely to them, hellhounds rounds were hugely important to the game's evolution, as they brought with them guaranteed max ammo drops.

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Usually, hellhounds aren't very difficult to dispatch, offering a bit of a reprieve for beleaguer zombie slayers. That said, the can be a nuisance if players are wielding weapons which need to be reloaded frequently.

Meuchler (The Darkest Shore)

Meuchler zombies from Call of Duty WWII

Though it's often forgotten by fans of the Black Ops subseries, Call of Duty WWII's take on the zombies formula managed to innovate without straying too far from what made the mode so popular in the first place. While many tired of it fairly quickly, it should be commended for staying true to the horror themes present in the initial World at War maps.

The Darkest Shore's primary boss enemies, the Meuchlers were terrifying, multi-armed monstrosities that leapt from the map's thick fog and attacked players with an unmatched ferocity. Easily one of the creepiest boss zombies of all time in terms of design and aesthetic, WWII's Meuchlers deserve more credit than they initially received.

Orda (Firebase Z)

The Orda boss fight in Call of Duty Black Ops Cold War's Firebase Z zombies map.

The Call of Duty zombies storyline has often flirted with the concept of Lovecraftian horror, with the most prominent example of that being Black Ops 3's Shadows of Evil map, but such inspiration can also be seen on the new map, Firebase Z. Should players make it to round 30, they'll be forced to defend a section of the map from the mysterious eldritch god Orda.

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A towering beast that's reminiscent of the Panzermorder from WWII zombies, the Orda stands far out of harm's way, is nearly impervious to most scorestreaks, and can take some serious coordination to take down.

Krasny Soldat (Outbreak)

Black Ops Cold War's Krasny Soldat zombies enemy.

Faster than a speeding bullet! More powerful than a locomotive! Able to leap tall buildings in a single bound! It's a bird! It's a plane! No, it's the Krasny Soldat from Black Ops Cold War's Outbreak mode.

Perhaps the single most intimidating boss zombie of all time, the Krasny Soldat was clearly designed for the wide-open terrain of Black Ops Cold War's new zombies mode. Nearly impossible to escape and brutally difficult to deal with in close quarters thanks to his flamethrower, the Krasny Soldat has likely ended more Outbreak runs than most players would care to admit.

Panzermorder (The Final Reich)

The Panzermorder boss zombie from Call of Duty WWII's The Final Reich zombies map.

The epic final boss fight of The Final Reich's main Easter egg in WWII zombies, the Panzermorder is a mortifying mass of bodies that perfectly represents the horrific overtones of the 2017 Call of Duty installment's undead slaughterfest. A hulking goliath that can only be taken down with repeated airstrikes, it's an utter nightmare to fight, particularly during the much harder "true" Easter egg.

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From the beefed-up Wustlings to the aformentioned Meuchlers, WWII zombies was full of horrors, but, in terms of sheer brawn, the Panzermorder stands almost unmatched.

Margwa (Shadows Of Evil)

The Margwa boss zombie from Call of Duty Black Ops 3's Shadows of Evil.

Prior to the release of Black Ops 3, Lovecraftian conspiracies and eldritch horrors had been hinted at within the zombies storyline, but they'd never actually been seen. That changed when Shadows of Evil was introduced, as it brought interdimensional terrors and half-human, half-squid hybrids to the forefront of the action.

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Under the command of the villainous Shadow Man, the three-headed Margwa was a brutish boss that could only be damaged when its mouths were open. Skilled players had to carefully aim at the monster's exposed maw to bring it down, making sure that every shot they took during that small window of time counted.

Brutus (Mob of the Dead)

Brutus, the boss zombie in Black Ops II's Mob of the Dead zombies map.

The hellish guardsman eternally watching over the damned souls locked in Black Ops II's demented version of Alcatraz island, Brutus is a terrifying figure famous for his enraged screams and merciless hatred for Mob of the Dead's four would-be escapees.

More than just a typical brute single-mindedly chasing down players with his club, Brutus has the ability to lock down things like perk machines and the mystery box, forcing players to spend points to unlock them again. Brutus returned—and was arguably more fiendish—in Black Ops 4's Blood of the Dead, though he'll always be best-remembered for his original appearance.

Panzersoldat (Origins)

The Panzersoldat, and armored zombie featured in Black Ops II's zombies mode.

Undoubtedly the most legendary boss zombie variant in Call of Duty zombies history, the Panzersoldat is an utter beast capable of ending any unprepared team's run. Making several appearances throughout Black Ops II and III and with an aforementioned spiritual successor appearing in Black Ops Cold War, the Panzersoldat is almost as widely-renown as the mode's famous hellhounds.

The Panzersoldat was made iconic thanks to his inaugural appearance in Black Ops II's Origins. Consistently appearing on round eight, he was a death sentence for hapless newcomers, and he acts as a genuinely imposing boss unless players have any of the four staffs.

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