All the 51 promotions that happened in the Chicago Fire season 12 finale

Chicago Fire teased some major shakeups ahead of its season 12 finale, and it did not disappoint. The show will look wildly different heading into season 13, largely due to the changes that were made within Firehouse 51's personnel.

Nobody got fired (thankfully), but a handful of promotions mean that there's going to be some potential openings when the show returns. Let's not get ahead of ourselves, though. There was so much going on during the season 12 finale that it was easy to lose sight of who now has what title, so we thought it'd be helpful to break down where the main 51 players stand as of now.

Wallace Boden is promoted to Deputy Commissioner

This is the one we all saw coming. Wallace Boden (Eamonn Walker) was confirmed to be leaving Chicago Fire (full time) at the end of the season, and there was no better circumstances under which he could leave than as the newly minted Deputy Commissioner of the city.

It was sad to see him leave, especially with Firehouse 51 members taking time out to voice how much he has meant to them over the years, but it's reassuring to know that we will still get to see him in a handful of season 13 episodes. A win all around, we'd say.

Christopher Herrmann is promoted to Battalion Chief

This is the curveball nobody saw coming. Kelly Severide (Taylor Kinney) was the one who filled in for Boden when he was taking a leave of absence, and it seemed as though he would be offered the gig full-time once Boden got promoted. This turned out to not be the case. Boden instead decided to go with the veteran Christopher Herrmann (David Eigenberg).

This makes sense on a few different levels. For one, Herrmann and Boden go way back. For another, Herrmann is one of the most experienced firefighters in 51, so it only seems natural that he would be able to put this experience to use as a mentor. There's also the hearing loss he suffered at the top of the season. It's probably for the best that he moves behind a desk rather than staying in the field.

Mouch is studying to take the Lieutenant exam

This is the one that warmed our hearts. Mouch (Christian Stolte) ended last season on death's door, but he managed to recover and find a new lease on life. He's in better shape, he's more aggressive in the field, and he's cognizant of making the most out of his final years with the firehouse.

There's no better way to cap off this transformation than making lieutenant. Mouch has never been one driven by rank, but he realizes he's as deserving of a promotion as anyone else, and he revealed that he's been studying to take the lieutenant exam in the season 12 finale. With Trudy (Amy Morton) in his corner, we're confident the character can pull it off and stand next to his buddy Herrmann as "Lt. Mouch."

Joe Cruz (Joe Minoso) is another character who could make Lieutenant in season 13, and then there's the aforementioned Severide, who didn't receive a promotion but feels primed to take on more responsibility as he becomes more of a 51 veteran. Who are you most excited to see in their new roles?