This year's highly-anticipated Arrowverse crossover event just got a lot more interesting, as it's been officially titled Elseworlds. DC fans who are in the know will likely perk up at the title, as it comes with some potentially major implications. This could mean big things are coming to The CW's little corner of the DC universe. Here's what DC had to say about the crossover in their announcement tweet, which came with a new poster for the event as well.

"It's official! This year's #DCTV crossover event will be titled "Elseworlds," coming to CW_TheFlash, CW_Arrow and TheCWSupergirl this December! #Elseworlds."

The Legends of Tomorrow will be skipping out on this year's event, but the other characters who will be appearing more than make up for it. Not only is Tyler Hoechlin returning as Superman, with Elizabeth Tulloch making her debut as Lois Lane, but Ruby Rose will also be making her debut as Batwoman. This marks the first ever appearance of the Gotham City hero in live-action. The poster features a red Bat Signal in the sky, hinting at the character's impending arrival.

As for what the title Elseworlds actually means, that's tough to say as it relates to the story being told in this crossover, but in the world of DC Comics, it refers to stories that take place outside of the main continuity, such as Gotham by Gaslight or Kingdom Come. They started out as "what if?" scenarios. One of the most popular of these tales is Superman: Red Son, which will at least partially inspire the story being told throughout Supergirl season 4. From 1989 to 2010, the Elseworld tales existed totally outside continuity. However, once DC launched the New 52 initiative, these tales were shifted to alternate versions of Earth within the larger DC universe.

Taking all of that into account, it presents some pretty interesting opportunities. Perhaps this is how they explain why Batman doesn't exist in the Arrowverse at all, paving the way for Batwoman to take his place? Another interesting wrinkle is that The CW has announced Sons of Anarchy and The Last Ship star LaMonica Garrett has been cast in the role of the Monitor, who played a big part in the Crisis on Infinite Earths storyline. Garrett will be playing Mar Novu, an extraterrestrial being of infinite power known as the Monitor who holds near infinite knowledge of the multiverse, which could come in handy for Barry, Oliver and Kara, as they're sure to have a lot of questions.

What that means for the crossover event remains to be seen, but this just became an unquestionably huge deal for DC fans. Elseworlds kicks off on Sunday, December 9 on The Flash, followed by Arrow on Monday, December 10 and Supergirl wraps things up on Tuesday, December 11. Be sure to check out the new poster for the Arrowverse crossover from the DC Twitter account for yourself below.