The gaming community was ablaze with excitement following the official reveal of the long-awaited and rumored Mortal Kombat 1, and though most have been focused on the captivating cinematic trailer that shows off the reset timeline created by Liu Kang, developer NetherRealm confirmed some interesting bits of info via an official press release (as relayed by Game Informer), such as the Kameo Fighter system.
It wasn't explained in too much detail, but with what is stated, it does seem like Mortal Kombat 1 will feature some sort of assist character mechanic, such as what you tend to see in squad fighters like Marvel vs. Capcom and Dragon Ball FighterZ.
The statement reads as follows, "We’re also introducing our Kameo Fighter system which brings a unique roster of partner characters into the mix, and we are looking forward to showing this feature." It's a vague statement admittedly; it doesn't specify how these partner characters will work or what exactly they will do.
However, since it's described as a separate list of "partner" characters, the most likely possibility is that they'll assist the central character in battle, probably via assist moves, or perhaps some additional buffs and abilities.
Ed Boon, Mortal Kombat co-creator and studio director, also lent credence to this possibility, tweeting about a player performing "Kameo Kombos" later this year. If so, this will be an interesting twist to the "assist move" mechanic, as there usually isn't a unique set of characters that purely function to lend a helping hand.
The most prominent example of this is probably Pokken Tournament, though there are surely others. This is a pretty clever idea as it allows NetherRealm to add a wider variety of interesting characters that players get to play with and enjoy, without having to commit to fully developing every single one.
Another interesting aspect of it is the "Kameo" name, which undoubtedly hints at the possibility of characters from other universes. As reported by TheGamer, it was claimed by a leaker that Homelander, from the hit Amazon show The Boys, and Peacemaker, from The Suicide Squad movie, would be guest characters in Mortal Kombat 1. Though it was assumed they'd be standard characters, as Mortal Kombat has added third-party licensed fighters before, it could be they're part of this new Kameo system.