'Legends of Tomorrow' season 2 spoilers, plot news: The Legion of Doom formed

"Legends of Tomorrow" season 2 will have a revamped lineup of both heroes and villains when it premieres in a few months. The addition of several characters to join the series regulars makes for an interesting new season. This development was announced at the San Diego Comic-Con Saturday, July 23.

The core team members who are all coming back for "Legends of Tomorrow" season 2 will be up against some familiar baddies hailing from The CW shows, "The Flash" and "Arrow." This group of villains will be known as The Legion of Doom. The group will include Reverse-Flash (Matt Letscher), Captain Cold (Wentworth Miller), Damien Darhk (Neal McDonough), and Malcolm Merlyn (John Barrowman).

Letscher will be coming to "Legends of Tomorrow" season 2 as a regular cast member, whereas Miller and Barrowman have been signed on to appear with recurring roles in other CW series as well.

Marc Guggenheim, the executive producer of the series, explained the inspiration behind this distillation of villains.

ComingSoon.net quoted Guggenheim as saying, "[W]e decided that the perfect antagonist for TV's first-ever team of Super Heroes would be TV's first-ever team of Super-Villains ... Being huge fans of the Challenge of the Superfriends, we've come to call this group our 'Legion of Doom.'"

On the side of the good and joining the mainstay heroes are the Justice Society of America (JSA) members: Rex Tyler a.k.a. Hourman played by Patrick J. Adams, an incarnation of the character Vixen to be played by newcomer Maisie Richardson-Sellers, and Dr. Nate Heywood a.k.a. Commander Steel who will be portrayed by new series regular, Nick Zano. The JSA was introduced into the series by Hourman when he appeared in the season 1 finale of "Legends of Tomorrow."

The three will be joined by another new trio of heroes announced during Saturday's panel: Obsidian, Stargirl a.k.a. Courtney Whitmore, and Dr. Mid-Nite. Casting for the last three characters has yet to be announced.

Obsidian is known as the son of Green Lantern Alan Scott who has the ability to form a formidable shadow. Whitmore inherited the Cosmic Staff from Starman and gained her abilities from it. She took on the identity of Stargirl when she became a member of the JSA. Dr. Mid-Nite, on the other hand, has the ability to see perfectly in the dark of night.

"Legends of Tomorrow" season 2 will debut on Oct. 13 on The CW.