Question: What supervillain appears in The Batman Adventures and from DC Comics?

Context articles: Jason Hall (writer)
The Batman Adventures: Mad Love
DC Comics
Harley Quinn
The New Batman Adventures
The Superman/Batman Adventures
Batman: The Animated Series
Roxy Rocket
Batman Beyond: Return of the Joker
The Batman Adventures

Jason Hall is a comic book writer.
 His works include the creator-owned graphic novel series "Pistolwhip" (nominated for multiple prestigious Harvey Awards and one of Time Magazine's Top 10 Graphic Novels of 2001), "Beware the Creeper" and "Trigger" for DC/Vertigo, "Batman Adventures", "Justice League Adventures", "Justice League Unlimited", "Superman", "Detective Comics", "Ben 10", "Samurai Jack", and "Dexter's Laboratory" for DC Comics, and "Star Wars" and "Hellboy Animated" for Dark Horse Comics.
The Batman Adventures: Mad Love is a one-shot comic book written by Paul Dini (writer on "" and "Batman Beyond") and Bruce Timm (executive producer on "The New Batman/Superman Adventures" and the co-creator of "Batman: The Animated Series").
 Set in the continuity of "The Batman Animated Series", it won an Eisner Award for "Best Single Story" in 1994.
 It was later adapted (with minor alterations for pacing) as an episode of the animated series "The New Batman Adventures".
DC Comics, Inc. is an American comic book publisher.
 It is the publishing unit of DC Entertainment, a subsidiary of Warner Bros.
 Entertainment, Inc., a division of Time Warner.
 DC Comics is one of the largest and oldest American comic book companies, and produces material featuring numerous well-known heroic characters including Superman, Batman, Wonder Woman, Green Lantern, the Flash, Aquaman, Hawkman, and Green Arrow.
 Most of their material takes place in the fictional DC Universe, which also features teams such as the Justice League, the Justice Society of America, the Suicide Squad, and the Teen Titans, and well-known villains such as the Joker, Lex Luthor, The Cheetah, Harley Quinn, Darkseid, Catwoman, Ra's al Ghul, Deathstroke, Reverse-Flash, Sinestro, Black Adam, and Brainiac.
 The company has also published non-DC Universe-related material, including "Watchmen", "V for Vendetta", and many titles under their alternative imprint Vertigo.
Harley Quinn (Harleen Frances Quinzel) is a fictional supervillain and occasionally antihero appearing in American comic books published by DC Comics.
 The character was created by Paul Dini and Bruce Timm, and first appeared in "" in September 1992.
 She later appeared in DC Comics' Batman comic books, with the character's first comic book appearance in "The Batman Adventures" #12 (Sept. 1993).
The New Batman Adventures (often shortened as TNBA) is an American animated television series based on the DC Comics superhero Batman, and is a continuation of the 1990s "".
 It was produced by Warner Bros.
 Animation and aired on The WB from September 13, 1997, to January 16, 1999.
 According to the reference book "Batman Animated", series writer Paul Dini originally wanted the new show to be titled Batman: Gotham Knights, but this idea was rejected by the other producers.
 To better adhere with the prior DVD sets of the original series, the DVD release of this series was titled "Batman: The Animated Series Volume 4 (From The New Batman Adventures)" and was given the opening theme from the prior series.
The Superman/Batman Adventures is a television series that aired on USA Network in 1995.
 It was later aired on Cartoon Network and Boomerang.
 The episodes were edited from various seasons of the Hanna-Barbera-produced "Super Friends", as well as Filmation's 1960s series "The New Adventures of Superman", "The Superman/Aquaman Hour of Adventure", and "The Batman/Superman Hour".
 "The Superman/Batman Adventures" included for the first time on American television the "lost episodes" of the 1983–1984 season of "Super Friends".
Batman: The Animated Series is an American animated television series based on the DC Comics superhero Batman.
 It was developed by Bruce Timm and Eric Radomski.
 Produced by Warner Bros.
 Animation, it originally aired on Fox Kids from September 5, 1992, to September 15, 1995, with a total of 85 episodes.
 For the final fifteen episodes, the series was given the on-screen title The Adventures of Batman & Robin, which was also used for reruns of earlier episodes.
 The series eventually spawned a continuation show, "The New Batman Adventures".
Roxy Rocket is a fictional character, a minor comic book supervillainess.
 Originally created in 1994 for "The Batman Adventures Annual" #1, a series published by DC Comics, based on "", Roxy was incorporated into "The New Batman Adventures" in the episode "The Ultimate Thrill", which first aired on September 14, 1998.
 Shortly thereafter, Roxy appeared in "Knight Time", an episode of "".
 Roxy later appeared in several comic books based on the TV show.
 In 2006, the character was introduced to the main DC Universe.
Batman Beyond: Return of the Joker (also known as Batman of the Future: Return of the Joker in Europe and Australia) is a 2000 American direct-to-video superhero animated film featuring the comic book superhero Batman and his archenemy, the Joker.
 It is set in the continuity of the animated series "Batman Beyond", in which Bruce Wayne has retired from crime fighting, giving the mantle of Batman to high-school student Terry McGinnis, and serves as a sequel to both "" and "The New Batman Adventures".
 As in the TV series, Will Friedle and Kevin Conroy star as Terry McGinnis and Bruce Wayne, respectively, and Mark Hamill, who voiced the Joker opposite Conroy in "Batman: The Animated Series" and "The New Batman Adventures", reprises his role.
The Batman Adventures was a DC Comics comic book series featuring Batman.
 It is different from other "Batman" titles because it is set in the continuity (and style) of "" as opposed to the regular DC Universe.