Not to be one of those 'too many comic book shows' guys but aren't they pushing it a little with all these comic book shows? So there will be at least 5 shows based on DC/Marvel. Agents of Shield, Gotham, Arrow, Flash & now Atom. While I do enjoy them & will watch them, having so many will potentially cause superhero fatigue in the general viewing audience.

The curious spinoff project featuring characters from both Arrow and The Flash is starting to come into focus, with details on three roles to be cast.

As previously reported, the CW spinoff — which may zip past the usual pilot process and be ordered straight to series — will star Arrow‘s Brandon Routh (who plays Ray/The Atom) and Caity Lotz (formerly Sara/Canary), as well as The Flash‘s Wentworth Miller (Leonard Snart/Captain Cold) and Victor Garber (Dr. Martin Stein aka half of Firestorm).

Rounding out the ensemble, TVLine has learned, are the following “mystery” characters — though we’ve put forth out best theories on the familiar heroes/foes being cast. (With reporting by Michael Maloney)

“THE TRAVELER” | Described as a “Han Solo-esque rogue who gets by with his charm, this hero hails from the future, and has journeyed back in time on a secret mission. His razor-sharp wit hides the pain of a man who has lived through serious conflict. He also harbors many secrets, always leaving both his teammates and the audience unsure of his true allegiances.

Quite Possibly Is Rip Hunter (pictured above), who first debuted in 1959 in the pages of DC Comics’ series Showcase and has popped up in continuity over the years. This Time Master has revealed in the past that “Rip Hunter” isn’t his real name – it’s an alias he uses so that his enemies can’t thwart his future efforts by killing him when he is a helpless infant in the past!

But Could Also Be Booster Gold — though he appeared in an episode of Smallville (played by Days of Our Lives‘ Eric Martsolf), and it’s been said the new characters have never been featured on a live-action show before — or Time Traveler, a powerful villain who’s gone up against the Legion of Super-Heroes.

“FEMALE WARRIOR” | This twentysomething Latina is pretty but unassuming, book smart and socially awkward by day. But by night, when she hears the cry of battle, her fury is ignited and she becomes a fierce warrior — so much so, that sometimes she can become a threat to others.

Quite Possibly Is a cross between Fury aka Helena Kosmatos (pictured), an Amazon heroine empowered by the ancient Furies, and Yolanda Montez, who assumed the role of Wildcat from her godfather, Ted Grant.

But Could Also Be Pantha aka Rosabelle Mendez, a short-lived member of the New Titans, or Tarantula aka Catalina Marie Flores, who hails from the pages of Nightwing.

“MYSTERY HERO” | An African-American male in his twenties will fill the role of a regular, street smart guy who unexpectedly gains powers, and then, as part of the team, regularly quips about the insanity of the situations.

Quite Possibly Is Virgil Ovid Hawkins, a high school student who was splashed with experimental chemicals after being caught in a gang war. Virgil emerged with electromagnetic powers, which he uses to fight crime as the superhero Static (pictured).

But Could Also Be Black Lightning (aka Jefferson Pierce) or Black Vulcan

The CW’s potential new Flash and Arrow spin-off is slated to feature a mashup of DC Comics heroes and villains that aims to take our generation’s super series to the next level.

The untitled drama—which is being developed by Arrow and Flash executive producers Andrew Kreisberg and Greg Berlanti, as well as Arrow boss Marc Guggenheim and Sarah Schechter—is tentatively slated to star Brandon Routh (Ray Palmer/The Atom), Wentworth Miller (Leonard Snart/Captain Cold), Victor Garber (Martin Stein/Firestorm) and Caity Lotz, though it’s unclear whether she’ll be portraying a new role since her Arrow character, Sara Lance, died earlier this season.

“For me, it honors all of the great team up movies, whether it’s Ocean’s Eleven or whether it’s the superhero books,” Berlanti tells EW. “That’s what it’s about. If you go back to the old westerns, there would be The Lone Gunman, but there would also be The Magnificent Seven. It’s very much in the spirit of those kinds of movies and shows.”

Berlanti—who is also executive-producing CBS’ Supergirl pilot with Kreisberg, Schechter and Ali Adler—stresses that the new project would be quite different than what we’re used to. “I only want to do them when I know that they’ll feel distinct from the other shows we’re doing,” he says. “This is really its own thing.”

One of the main burning questions after the project’s announcement was why Robbie Amell was missing from the cast list, considering he makes up the other half of Firestorm, Ronnie Raymond. Unfortunately, it sounds like bad news could be on the horizon as Berlanti admits there is a particular reason for his absence, but “I can’t say why.”

The new super drama, which is not part of the current pilot season, was first mentioned by CW president Mark Pedowitz at the Television Critics Association’s semi-annual press tour in January. Get more on that here.

EXCLUSIVE: Another popular recurring DC character from the Arrow-Flash universe is boarding the CW’s proposed spinoff from the two superhero dramas. The new Flash villainous duo of Captain Cold/Heat Wave will be staying intact as Dominic Purcell is joining Brandon Routh, Wentworth Miller, Victor Garber and Caity Lotz in the superhero team-up show from Arrow creators Greg Berlanti, Andrew Kreisberg and Marc Guggenheim.

Purcell will reprise his role as Mick Rory, a pyromaniac who finds an outlet for his obsession with fire when he teams up with Leonard Snart/Captain Cold (Wentworth Miller) and becomes the villain known as Heat Wave. The new project, eyed for a midseason launch next season, extends the Flash reunion of Prison Break stars Miller and Purcell and would mark the first series regular gigs for both since the cult Fox drama.

Routh and Garber also are set to reprise their popular Arrow/Flash characters — Arrow‘s Ray Palmer/The Atom (Routh) and Flash‘s Dr. Martin Stein (Garber). Because her Arrow character Sara Lance was killed off, with her sister Laurel Lance (Katie Cassidy) taking over as the Black Canary, it is still TBD whether Lotz will play the same or new superhero on in the spinoff.

Speaking of Flash dynamic duos, Garber’s Stein is flying solo on the new show for now as Robbie Amell, who has played his other half, Firestorm, did not sign for the project. As we previously revealed, the spinoff series will include three major DC Comics characters who have never appeared in a TV series.

The cast of the as-yet untitled spinoff of "The Flash" and "Arrow" has a new DC Comics superhero in the mix, as first reported by Deadline: Hawkgirl, played by relative newcomer Ciara Renée.

The Hawkgirl/Kendra Sunders character is described as, "a young woman who is just beginning to learn that she has been repeatedly reincarnated over the centuries. When provoked, her ancient warrior persona manifests itself, along with wings that grow out of her back, earning her the moniker Hawkgirl."