Characters from the DC comics

Below is a list of characters who originally appeared in the DC comics multiverse prior to the episode's airing, by appearance.

Arrow
Characters first appearing in Arrow:

Comic book tie-in characters

 * 1) Khem-Adam ("Following")
 * 2) Ravan Nassar ("Haunted") *
 * 3) Lyle Bolton ("Assurances")

Novel tie-in characters

 * 1) Father Trigon/The Devil ("Arrow - Vengeance")

Upcoming characters

 * Christopher Chance/Human Target

Notes:
 * 1) Thea is based on the comic book character, Mia Dearden, the second person to take on the mantle of Green Arrow's sidekick, Speedy, and the first to be a female. Though the name "Thea Queen" originates from the show.
 * 2) Even though Laurel is the actual version of Black Canary in Arrow, her younger sister, Sara Lance, who is an original character specifically created for the show and was previously knows as "The Canary", is also based in part on the same character. Sara is also a version of another comic book character, the White Canary.
 * 3) Felicity's codename had been used in the comics only once, but by another character. It was recently introduced as "Overwatch-One", the code name of Terry Sloan in Earth 2: Society series.
 * 4) Even though Malcolm is the actual version of Merlyn in Arrow, Tommy Merlyn, who is in part an original character specifically created for the show, is also based on the same character.
 * 5) Even though the character originates from the comics, his real name remained unknown. Unlike the comics, on the show he is given a real name, Winnick Norton.
 * 6) In the comics, Isabel is also known as "The Queen". Ravager, which is the alias she is informally given on the show, is the alter ego of several comic book characters, most of them related to Slade Wilson.
 * 7) Sebastian's parents are both based on comic book characters as well. Sebastian Sangre is based in part on Sebastian Blood VIII who is the father of Sebastian Blood IX. Sangre means blood in Spanish. Maya Resik is based in part on Mother Mayhem. Both women who adopted the title, Anna Resik and May Bennett, were mothers of different Sebastian Bloods.
 * 8) Sin's real first name on the show has been revealed to be Cindy with her last name being still unknown. In the comics, her name is Cynthia and she got the surname "Lance" after she got adopted by Black Canary.
 * 9) Steelgrave is seemingly based on a minor Green Arrow foe, Professor Steelgraves (first name unknown), who is also mainly a weapon smuggler.
 * 10) Even though Werner is the actual version of Count Vertigo in Arrow, the unnamed predecessor known as The Count, who first appeared in , is also based in part on the same character.
 * 11) Even though his first name was changed to "Curtis" for the show, he is based on the comic book superhero Michael Holt, the second Mr. Terrific.
 * 12) Even though the character originates from the mainstream DC comics, his last name was never revealed, as he was only known by his first name. Unlike the comics, in Arrow: Season 2.5 he is given a last name as well, Nassar.
 * 13) Even though in the comics his first name is unknown, he is based on a character known as Master Jansen who first appeared in Flash #218.
 * 14) In the comics, Konstantin Kovar was the father of Leonid Kovar, a Russian superhero known in the comics as Red Star. Konstantin eventually turned out to be a villain, and one of the masterminds behind "meta men".
 * 15) Richard is based on The Seattle Slasher, an otherwise unnamed serial killer from the mini-series Green Arrow: The Longbow Hunters, who had victimized prostitutes and encountered Oliver Queen, who was then residing in Seattle rather then Star City.

The Flash
Characters first appearing in The Flash:

Comic book tie-in characters

 * 1) Nathan Bliss/Mr. Bliss ("The Strongman Cometh")

Referenced characters

 * 1) Evan Gibson
 * 2) Cameron Scott
 * 3) Ralph Dibny
 * 4) Grant Emerson
 * 5) Will Everett
 * 6) Bea da Costa
 * 7) Mal Duncan
 * 8) Joker ("The Chronicles of Cisco")

Upcoming characters

 * Sam Scudder/Mirror Master (untitled fourth episode)
 * Rosalind "Rosa" Dillon/The Top (untitled fourth episode) *
 * Savitar (unknown episode)

Notes:
 * 1) Even though Eobard is the actual version of Reverse-Flash in The Flash, Eddie Thawne, who is in part an original character specifically created for the show, is considered to be partly based on the same character, due to the similarity of their names.
 * 2) Even though the character originates from the comics, his last name was never revealed, as he was only known by his first name or his alias. Unlike the comics, on the show he is given a last name as well, Gibran.
 * 3) In the comics, Baez's first name is actually Lashawn but it was changed to Shawna for the show.
 * 4) Brie is a reimagining of the villain known as the Bug-Eyed Bandit, who in the comics is a male and is named Bertram Larvan.
 * 5) Al Rothstein is also the name of the Earth One equivalent of the character. This is in addition to a previous unrelated character with the same name, who was mentioned in.
 * 6) In the mainstream DC comics, the "Zoom" or sometimes "Professor Zoom" alias is usually connected to the Reverse-Flash identity. The first has mostly been used by Hunter Zolomon. For a large part of the second season, Zolomon pretended to be Jay Garrick/The Flash, who is a different character altogether.
 * 7) In the mainstream DC comics, King Shark's real name is Nanaue.
 * 8) In the mainstream DC comics, there are two different versions of Doctor Light, with the second one being a female of Asian origin. Though it is not Linda Park but Kimiyo Hoshi.
 * 9) In the mainstream DC comics, Hath-Set and Vandal Savage are two separate characters, with only the former being involved in Hawkman and Hawkgirl's origin, but in this version they are combined.
 * 10) Even though the character originates from the comics, his real name was never revealed, as he was only known by his aliases, "The Turtle" or "Turtle Man". Unlike the comics, on the show he is given an actual name as well, Russell Glosson.
 * 11) In the comics, "Reverb" and "Rupture" are the aliases of Armando Ramone, the brother of Paco Ramone a.k.a. Vibe (a former version of Francisco "Cisco" Paco Ramon).
 * 12) For the most of Season 2, Hunter Zolomon masqueraded as Jay Garrick. However, the real Jay Garrick was revealed as Hunter's masked prisoner in.
 * 13) Rosa is a reimagining of the villain known as the Top, who in the comics is a male and is named Roscoe Dillon.

Constantine
Characters first appearing in Constantine:

Referenced characters

 * 1) First of the Fallen
 * 2) Cedella
 * 3) Judith *

Notes:
 * 1) In the comics, Nommo is also known as Doctor Mist. In the New 52, his real name is established as Nommo Balewa.
 * 2) In the comics Judith is a minor character and a member of the Newcastle Crew. She has made only a few small appearances and most of the time she is just mentioned by other characters. Her last name is unknown.

Vixen
Characters first appearing in Vixen:
 * 1) Mari McCabe/Vixen *

Referenced characters

 * 1) Anansi

Notes:
 * 1) Even though Mari is the actual version of Vixen, her ancestor, Amaya Jiwe, who is an original character specifically created for the show, is also based in part on the same character.

DC's Legends of Tomorrow
Characters first appearing in DC's Legends of Tomorrow:
 * 1) Rip Hunter
 * 2) Chronos *
 * 3) Valentina Vostok
 * 4) Mikhail Arkadin
 * 5) Grant Wilson/Deathstroke *
 * 6) Jon Valor
 * 7) Talia al Ghul
 * 8) Per Degaton
 * 9) The Pilgrim
 * 10) Rock *
 * 11) Rex Tyler
 * 12) Nate Heywood
 * 13) Henry Heywood/Commander Steel
 * 14) Dr. Mid-Nite
 * 15) Todd Rice/Obsidian
 * 16) Courtney Whitmore/Stargirl
 * 17) Baron Krieger/Übermensch *

Referenced characters

 * 1) Kanjar Ro
 * 2) Fadir Nasser
 * 3) Onyx
 * 4) Tigris
 * 5) Quentin Turnbull
 * 6) Hannibal Hawkes

Notes:
 * 1) In the comics Chronos was a supervillain obsessed with time, and an enemy of Ray Palmer, the Atom. In his different incarnations he exhibited mastery of chronokinesis, time travel, and time-related gadgets. However, while multiple people donned the mantle of Chronos, Mick Rory was not one of them.
 * 2) In the comics, Grant is known as either Ravager or Legacy, but in the show he takes on the moniker of Deathstroke, like his father, Slade.
 * 3) In the comics, Sgt. Rock's real name is Frank Rock, though on the show it hasn't been mentioned yet.
 * 4) In the comics Albrecht Krieger, also known as Captain Nazi was a genetically altered supervillain, while Ubermensch was a legacy name of two unrelated villains, who were altered to have a set of powers identical to one Krieger displayed in the series.

Freedom Fighters: The Ray
Characters first appearing in Freedom Fighters: The Ray:

Upcoming characters

 * Raymond "Ray" Terrill/The Ray (unknown episode)
 * Uncle Sam (unknown episode)