Mortal Kombat has established itself as one of the most popular fighting game franchises out there. With its brutal combos and gory finisher moves, it has attracted fans from all over. The roster in each game has a wide variety of characters from a cocky Hollywood actor to Demi-Gods, but the best part about Mortal Kombat is often the extra characters that show up to join the tournament.

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Over the years, the Mortal Kombat games have featured a number of hidden secret characters that are canon to the storyline, but more recently, the games began to get visits from characters from other realms. From the God of War Kratos to the law-enforcing Robocop, some of the most well-known fighters and combatants across multiple fictional universes are making their way to the Earthrealm for a fight.

9 Alien Vs. Predator

Alien Vs Predator

Mortal Kombat X brought one of science fiction's most famous pairs together for another bout. Though they started in separate franchises, the Xenomorph from Alien and the Predator from Predator have clashed across several movies, comics and books.

The greatest hunter and their ultimate prey fit perfectly into the MK universe with their brutal, gruesome attacks and vicious nature. Though they can cause havoc among the rest of the roster of fighters, the question of which is better could finally be answered by facing them against each other.

8 The Terminator Came Back...To Fight

The Terminator

This time-traveling cyborg became a franchise traveling cyborg in Mortal Kombat 11 as he joined the roster as a DLC character. Taking on the form of the older Arnold Schwarzenegger from Terminator: Dark Fate, but still brings all the brutality and precision of the cyborg from the movies.

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The "ultimate killing machine" even melts his human appearance at low health to reveal the metallic body underneath. It is great to see one of the world's most prominent action movie stars appear in a fighting game so he can face off against another 80s action star that shows up.

7 John Rambo Adds More Numbers To His Killcount

Rambo

Also appearing as a DLC character in Mortal Kombat 11, Sylvester Stallone's John Rambo entered the tournament with his bandana and bow. Though Schwarzengger's appearance as The Terminator is his older look, Stallone's Rambo gets the youthful treatment, taking his appearance from First Blood, First Blood: Part II, and Rambo III.

The two stars didn't face off in The Expendables the way fans might have wanted, but they can now get that satisfaction pitting the US Special Forces soldier against the futuristic cyborg.

6 Kratos Finished With Greek Gods And Came To Fight

Kratos in Mortal Kombat

The anti-hero of the God of War series joined the fray in 2011 as a guest character on the PlayStation 3 and PlayStation Vita versions of Mortal Kombat (2011). Kratos uses his trademark "Blades of Chaos" as well as other weapons from his arsenal like the "Bow of Apollo" and "Head of Helios".

He was the first guest character from another video game to appear in Mortal Kombat. The popular PlayStation character was a draw for fans as his combo-heavy combat was a perfect fit for the fighting franchise.

5 Leatherface vs. Jason Voorhees

Leatherface and Jason Voorhees

In another face-off between two iconic characters, fans get to play as two serial killers with Leatherface and Jason Voorhees in Mortal Kombat (2011). Leatherface, from the Texas Chainsaw Massacre movies, is a formidable opponent fully utilizing his chainsaw and mallet to split, cut, and crush his poor opponent to bits.

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The ruthless killing machine Jason Voorhees, from the Friday the 13th franchise, uses his brute strength and machete to dominate opponents. His powerful attacks are no longer limited to teens in the woods and his trademark mask never comes off, even in a fatality.

4 The Joker Doesn't Need The Batman

The Joker

The Clown Prince of Crime laughed his way into Mortal Kombat 11 after being a character in the Mortal Kombat vs. DC Universe game. Though that version came with all the other DC characters like Batman and Wonder Woman, The Joker went solo for his second outing in the franchise.

He incorporated his trademark cynical humor and dastardly attacks that were leveled up in the gore factor for the game. He is an evil genius with an insatiable hunger for violence and murder, meaning he fits right in with the rest of the characters in the tournament.

3 Go With Robocop, Dead Or Alive.

Robocop-1

The cyborg cop from the futuristic dystopian city of Detroit made his way into the tournament in Mortal Kombat 11 as a DLC character. His unrelenting need to squash criminals makes him a savage opponent as he uses his gun, flamethrower, and riot shield to beat down his opposition.

His kills in the movies were already gory, and some fan edits make them even more so, meaning his unforgiving combat style fits in perfectly with Mortal Kombat's fatality finishers. His finishers in the game are even direct references to kills from the first movie.

2 Spawn Emerged From Hell For A Fight

Spawn

The Anti-hero from the comics, movies, and cartoon shows appeared in Mortal Kombat 11 as the final DLC character. His story is already a gory and brutal one, and he takes no prisoners when dealing out his own form of justice.

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Aside from using his superior strength and preferred weapons, guns, Spawn also summons Hellfire and other abilities in order to demolish enemies. Spawn is also featured in the Soul Calibur series, but he finds a more appropriate, gory home with Mortal Kombat.

1 Freddy Krueger Made Dreams Come True

Freddy Krueger

A severely missed opportunity was having Freddy Krueger, from the Nightmare on Elm St franchise, face off against Jason Voorhees, as they do in the movies. While Voorhees joined Leatherface in Mortal Kombat X a few years later, Freddy joined the fighting roster in Mortal Kombat (2011).

He was given a second clawed glove for purposes of the game and was voiced by the iconic actor Robert Englund himself. The horror movie icon did not let fans down with gory fatalities, and he was also the first character from a movie franchise to be in Mortal Kombat.