Characters from the DC comics

Below is a list of characters who originally appear 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
 * 2) Ravan Nassar ("Haunted") *
 * 3) Lyle Bolton

Referenced characters

 * 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 codename 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, Leonid Kovar is a Russian superhero known as Red Star. Even though he shares his last name and nationality with his comic book counterpart, his first name hasn't been revealed on Arrow.

The Flash
Characters first appearing in The Flash:

Comic book tie-in characters

 * 1) Nathan Bliss/Mr. Bliss

Referenced characters

 * 1) Evan Gibson
 * 2) Cameron Scott
 * 3) Ralph Dibny
 * 4) Grant Emerson
 * 5) Will Everett
 * 6) Bea da Costa
 * 7) Mal Duncan

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. Jay Garrick/The Flash is considered to be an altogether separate character from Zolomon rather than just his fake identity.
 * 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).

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

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) Cassandra Savage *
 * 11) Rex Tyler

Referenced characters

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

Upcoming characters
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) Cassandra is an amalgamation of two daughters of Vandal Savage from different continuities: Scandal Savage of New Earth, with whom she shares masterful training under her father's tutelage; and Kassidy Savage from Prime Earth, who has a somewhat similar name and is a heroic character.