The Dark Knight in MK vs DCA Polygon Evo interview with NetherRealm Studios' Ed Boon is again drawing attention toward the likelihood of guest character(s) in 2015's Mortal Kombat X.

The profitable return of crossover fighters hasn't been much of a secret. As well as various references on Twitter -- Boon made guest character considerations known to various outlets during last month's E3 launch [Related Article: E3 2014: Gamespot Full Match Videos & Demo Stream].

Answering questions about a possible return crossover between NetherRealm's two established fighting franchises - Boon leaned toward the negative, "I'd be hard-pressed to have a DC character as a downloadable character in Mortal Kombat X."

This, of course, goes against the grain of Scorpion making the leap to Injustice: Gods Among Us, but there's an explanation for that rooted in the differences between the two franchises. "The main reason is, I have no desire to cut Batman's head off. I have no desire to kill Superman."

No Rematch: Batman won't be evening the score with Scorpion in 2015.

2008's Mortal Kombat versus DC Universe infamously bumped up against the non-lethal traditions of DC superheroes. The solution: introducing "Heroic Brutality" as a survivable alternative to Fatality finishers, The compromise remains a contentious subject for the more bloodthirsty Mortal Kombat purists.

No such censorship was afforded to Kratos or Freddy Krueger -- 2011 guest characters who both faced the full force of Mortal Kombat's deadly violence. This compliance won't score either character a return visit, though. Boon scratched off the PS3-exclusive God of War on Twitter, where he's also discussed looking for something new [Related Article: Who's Next? Ed Boon's Mortal Kombat X Character Deadpool!].

Popular speculation ranges everywhere from near-misses like Sweet Tooth and Spawn -- to horror movie icons like Jason Voorhees and The Predator! While documenting references picked up by fans, Mortal Kombat Online threw an upcoming 2015 Warner film reboot that also poses interesting possibilities.

What's clear is that guest characters are here to stay. Ed Boon has frequently cited Freddy Krueger and Scorpion as the highest selling/most downloaded DLC of their respective games.

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