By Bryan Smith on June 20, 2016 at 8:58pm
Speaking with IGN, NetherRealm creative director Ed Boon discussed their DLC plans for "Injustice 2" (well before the game is out and only a few days after being revealed) in what he describes as "more aggressive" with DLC.
One of the things we’ve been doing, trying to do more and more with every game… is to support it for a longer period of time. With DLC characters, we’ve had four with Mortal Kombat , six with Injustice, eight with Mortal Kombat X, and with Injustice 2 we plan on continuing that pattern. it will certainly be more aggressive than we’ve been in the past. Ed Boon
Boon also described the gear system, the system that allows you to customize your fighters, which may implement a "pay-to-unlock" model. This may be similar to the Gem feature in "Street Fighter X Tekken."
We have ideas in our head of the things we’d like to consider but certainly haven’t like nailed down this is going to be the way to do it. Ideally to me the whole purpose of this feature is customization, longevity and ongoing molding of your character so to speak.
The current roster for the game hasn't been revealed yet (game was only just announced and won't come out until 2017), so we can expect a lot of DLC characters but not the exact number until later.