Since its debut in Call Of Duty: World At War, the Zombies mode has become a staple of every Treyarch game of the massive franchise. Zombies would then become a mode in other games with different spins. The story, plethora of complex maps, and lore behind the Zombies' interconnected worlds have turned them into reasons to own Call Of Duty more than the actual game.

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One reason fans always return to Zombies is the celebrity maps. Typically, each game will feature at least one map featuring an all-star cast to play as and/or fight. Some of these guest star appearances are so beloved that fans wish that Activision would just make a standalone Zombies game about them.

Call Of Duty: Black Ops (2010) - Call Of The Dead

Michael Rooker, Sarah Michelle Gellar, Danny Trejo, Robert Englund, and George A Romero in Call Of Duty Black Ops' Call Of The Dead

The first-ever celebrity map was Call Of The Dead which features Freddy Krueger himself: Robert Englund, Danny Trejo, Sarah Michelle Gellar swapping from vampires to zombies, and Michael Rooker the same year he debuted on The Walking Dead.

These four horror icons are battling another icon; George A. Romero, the famous director that revolutionized zombie movies is the boss zombie. Horror fans and gamers alike get a lot of joy out of this map.

Call Of Duty: Black Ops II (2012) - Mob Of The Dead

The four mobsters in Call Of Duty Black Ops II Mob Of The Dead

Four mobsters stuck on Alcatraz Island with an endless legion of the undead chasing them. Said mobsters are played by Ray Liotta, Joe Pantoliano, Michael Madsen, and Chazz Palminteri. That alone sounds like the best mobster cast since Goodfellas which is why Mob Of The Dead remains a favorite of Black Ops II.

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So much so that these mobster characters would be referenced in one of Black Ops III's Zombies maps if one pays close attention.

Call Of Duty: Advanced Warfare (2014) - All Zombies Maps

Oz, Kahn, Lilith, Decker, and Lennox in Call Of Duty Advanced Warfare Exo-Zombies

The first of the Warfare series by Infinity Ward to embrace the Zombies mode. It was also the first to feature the celebrity cast in multiple maps instead of just one. The cast of John Malkovich, Jon Bernthal of The Punisher series and The Walking Dead fame, Rose McGowan from Scream and Charmed, and the late Bill Paxton of Aliens appear in all maps in an evolving story.

Later, John Malkovich was replaced with none other than the Evil Dead star: Bruce Campbell. With the exo-suit abilities and unique zombie mechanics, Advanced Warfare brought new life to Zombies. This game rivals Call Of The Dead in bringing so many horror legends together.

Call Of Duty: Black Ops III (2015) - Shadows Of Evil & Revelations

The Shadows Of Evil crew, Monty, and Shadow Man in Call Of Duty Black Ops III Zombies

In the spiritual successor to Mob Of The DeadShadows Of Evil features the mysterious Shadow Man recruiting four sinful souls to battle the undead. The four include a magician played by Jeff Goldblum, who's best known for Jurassic Park and The Fly, Ron Perlman, Heather Graham, and Neal McDonough.

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Robert Picardo of Star Trek: Voyager plays the Shadow Man and - much to the shock of fans - directly ties into the main Zombies storyline featuring Dempsey, Takeo, Richtofen, and Nikolai when he returns in Revelations. Also appearing in Revelations is the reveal of Dr. Monty's face which happens to be Clockwork Orange star: Malcolm McDowell.

Call Of Duty: Infinite Warfare (2016) - All Zombies Maps

Kevin Smith, Elvira, and David Hasselhoff in Call Of Duty Infinite Warfare Zombies

Unlike other Zombies modes, the celebrities are instead villains, companions, or guides on every map but can be playable via a special unlocking process. These include David Hasselhoff, Cassandra Peterson a.k.a. Elvira, and Paul Reubens who has been the recurring villain in every map.

With Infinite Warfare's Zombies mode embracing the cheesy and over-the-top tone of Return Of The Living Dead, these personalities fit well within the context of the maps. There are also some famous voices for the playable characters including Seth Green and Ike Barinholtz. On one map, Kevin Smith ends up being playable.

Call Of Duty: WWII (2017) - All Nazi-Zombies Maps

Olivia, Jefferson, Drostan, and Marie gazing at the airship in Call Of Duty WWII Nazi Zombies

Homaging Return To Castle Wolfenstein, the Nazi Zombies mode of Call Of Duty: WWII brings a more grounded and horror take on the Zombies mode. In a way, it takes things back to the original Zombies mode in World At War.

This is where it features Ving Rhames - who is in Zack Snyder's Dawn Of The Dead -, David Tennant of Doctor Who fame and fought vampires in Fright Night, Elodie Yung who some might know as Elektra in the Netflix Marvel Universe, and Kathryn Winnick fresh off her success on Vikings.

Call Of Duty: Black Ops 4 (2018) - Dead Of The Night

Gideon, Mirela, Godfrey, and Warwick firing at the zombie horde in Black Ops 4 Dead Of The Night

Keifer Sutherland, Charles Dance who played a vampire in the underrated Dracula Untold, Helena Bonham Carter, and Brian Blessed battling a zombie infestation in a massive Gothic mansion. Adding in werewolves, Dead Of The Night harks back to classic Universal monster movies in tone, atmosphere, and setting.

The cast really embraces that era of horror and all of them give great performances. Helena Bonham Carter is easily the funniest while Charles Dance feels straight out of those movies. Obviously, there is a lot more action since it is a Call Of Duty map.

NEXT: Call Of Duty: 10 Best Boss Zombies In Franchise History, Ranked