For the first time ever for a Batman game, the ESRB has given an upcoming title a “M for Mature” rating. That means things are going to get pretty intense in Batman: Arkham Knight.

IGN reports that game developer Rocksteady has announced that Batman: Arkham Knight, the last installment in its Batman: Arkham series, has earned an "M for Mature" rating, the equivalent of an R-rating for a movie. All previous entries, Batman: Arkham Asylum and Batman: Arkham City, as well as Batman: Arkham Origins and Batman: Arkham Origins Blackgate, were all rated “T for Teen.” While Rocksteady did recognize that the more severe rating might cause some of its fans to miss out on the game, it wouldn't have changed the game just to get the rating down.

Sefton Hill, Rocksteady's founder, explained that while the “M for Mature” rating does limit things, if the studio was to take out some of the elements that required that rating, it would have taken away from the story.

I'm not blind to the fact that [the M rating] does mean some fans will miss out. I don't want to be oblivious to that fact. It would have been wrong to water down the game and deliver a story we didn't believe in to keep the game 'mass market' or enable it for more people. We feel that's the wrong way to go about it. We said we love the story and we don't want to jepoardize [sic] that.

While no game developer ever wants to take away from the story of its game, it makes sense that this story in particular would be close to Rocksteady's hearts, as it is the last game of its Arkham trilogy (the Arkham: Origins games were developed by Warner Bros. Montreal and Armature Studio).

Just what elements in Batman: Arkham Knight brought about the more severe rating remain to be seen, but could give some credence to the idea that at some point we'll actually play as the Arkham Knight himself, and wield guns for the first time. Either that, or the violence is ramped up so immensely that it hinges on an R-rated Batman adventure.

Batman: Arkham Knight will be available on the Xbox One, PC and PlayStation 4 on June 2.