NetherRealm’s newest fighter, based entirely in the DC universe, stands to gain from the lessons learned during Mortal Kombat’s development. Most recently, the studio has unveiled that one of their regrets in MK was that players who’d purchased a downloadable character could not use that character against individuals who hadn’t purchased the same character. This was also something Capcom noted as an issue with its initial release of Marvel Vs. Capcom 3, and the reasoning they provided for why Ultimate Marvel Vs. Capcom 3 was actually a thing.
In the interest of fixing that, rather than including on-disc DLC, NetherRealm is working on a way to “push” a character’s data to a player’s console, such that, even if the player hasn’t paid for and downloaded that fighter, they will be able to play against the new combatant in online matches.
Mortal Kombat was a tremendous success as a fighting game, but its online multiplayer was by far its weakest component due to inescapable lag. If NetherRealm can avoid that with Injustice and implement its idea to push DLC characters to keep from fragmenting the online community, it seems like they may very well have a hit on their hands.