Once regarded an improbable oddity; the fighting game guest character has become an industry standard. The invasion of outside forces remains a controversial topic for hardcore fans of any series: Mortal Kombat has become a seasoned veteran of the crossover concept, accepting fights at home and abroad.

Kombatants were first establishing their crossover credentials as far back as the nineties. Characters like Sub-Zero and Raiden have lodged appearances in various series, including: NBA Jam, Unreal Tournament and The Grid. Scorpion made the latest Kombat crossover earlier this year, appearing as a Jim Lee designed downloadable guest in NetherRealm Studios' superhero fighter: Injustice: Gods Among Us. The ninja from Hell is expected to be among the pack-in content in November's Ultimate Edition.

In 2011, Mortal Kombat took a turn playing host to two well known guest fighters: Freddy Krueger (DLC) and Kratos (PS3 exclusive).

While it was the widely available, downloadable horror icon [Krueger] who proved to be a nightmare for diehard fans -- it turns out Sony's God of War was potentially ripe to be replaced by another choice.

Discussing various topics with fans, including the viability of a horror movie fighting game; Creative Director Ed Boon (@noobde) revealed Sony icon Sweet Tooth was considered for what would have likely been a Sony exclusive guest spot!

Like Kratos; the clown-faced combat racer is a creation of David Jaffe. Serving as murderous mascot to the Twisted Metal series -- Sweet Tooth is best known for laughing his way through vehicular slaughter unleashed by his ice cream van of doom.

A preference for being behind the wheel hasn't stopped Sweet Tooth venturing into other combat domains. In 2003, he battled beasts in mech form as a guest in War of the Monsters. Leaving the cockpit a year after missing out on Mortal Kombat; the killer clown entered the arena of man-to-man fighting in the party mixed PlayStation All-Stars Battle Royale.

As Kratos proved [read more]; NetherRealm would've been more than up to the task of collaborating on an iconic portrayal of Sweet Tooth. Better still: in Injustice: Gods Among Us, they even showed just how well an over-the-top, vehicle-based attack can work in a fighting game via Batman's Batmobile super! Then there's the story mode...

While we can't whole heartedly endorse the inclusion of guest characters in Mortal Kombat, we also can't deny it would've been an interesting choice for a Sony exclusive! With his home in Greek inspired mythology, Kratos proved a thematically appropriate final cut just the same.

Is Sweet Tooth the guest Kombatant for you? Have somebody else in mind? Sign up and join the conversation in the Mortal Kombat forum!