Question: in Batman: Under the Red Hood John DiMaggio was what fictional supervillain created by Bill Finger

Context paragraphs:
Penguin (character): The Penguin (Oswald Chesterfield Cobblepot) is a fictional supervillain appearing in American comic books published by DC Comics, commonly as an adversary of the superhero Batman.  The character made his first appearance in "Detective Comics" #58 (December 1941) and was created by Bob Kane and Bill Finger.  The Penguin is one of Batman's most enduring enemies and belongs to the collective of adversaries that make up Batman's rogues gallery.

Riddler: The Riddler (Edward Nigma) is a fictional supervillain appearing in American comic books published by DC Comics, commonly as an adversary of the superhero Batman.  The character made his first appearance in "Detective Comics" #140 (October, 1948) and was created by Bill Finger and Dick Sprang.

Isbisa: Isbisa is a fictional supervillain appearing in American comic books published by Marvel Comics.  He first appeared in "All Winners Comics" vol.  1, #19 (Fall 1946), published by Marvel predecessor Timely Comics during the 1940s period fans and historians call the Golden Age of Comic Books.  He was created by writer Bill Finger and one or more of the five artists who contributed one or more chapters to his 44-page debut story.

Batman in film: The fictional superhero Batman, who appears in American comic books published by DC Comics, has appeared in various films since his inception.  Created by Bob Kane and Bill Finger, the character first starred in two serial films in the 1940s, "Batman" and "Batman and Robin".  The character also appeared in the 1966 film "Batman", which was a feature film adaptation of the 1960s "Batman" TV series starring Adam West and Burt Ward, who also starred in the film.  Toward the end of the 1980s, the Warner Bros. studio began producing a series of feature films starring Batman, beginning with the 1989 film "Batman", directed by Tim Burton and starring Michael Keaton.  Burton and Keaton returned for the 1992 sequel "Batman Returns", and in 1995, Joel Schumacher directed "Batman Forever" with Val Kilmer as Batman.  Schumacher also directed the 1997 sequel "Batman & Robin", which starred George Clooney.  "Batman & Robin" was poorly received by both critics and fans, leading to the cancellation of "Batman Unchained".

Joker (character): The Joker is a fictional supervillain created by Bill Finger, Bob Kane, and Jerry Robinson who first appeared in the debut issue of the comic book "Batman" (April 25, 1940), published by DC Comics.  Credit for the Joker's creation is disputed; Kane and Robinson claimed responsibility for the Joker's design, while acknowledging Finger's writing contribution.  Although the Joker was planned to be killed off during his initial appearance, he was spared by editorial intervention, allowing the character to endure as the archenemy of the superhero Batman.

Red Hood and the Outlaws: Red Hood and the Outlaws is a superhero comic book published by DC Comics.  Commissioned in response to the growing popularity of the character of Jason Todd, a former protege of Batman who took a turn as a villain following his resurrection, the book depicts Jason's continued adventures as the Red Hood, on a quest to seek redemption for his past crimes, forming a small team with two of his fellow anti-heroes.

Batman: Under the Red Hood: Batman: Under the Red Hood is a 2010 American animated superhero direct-to-video film produced by Warner Bros.  Animation and released by Warner Home Video.  It is the eighth feature in the DC Universe Animated Original Movies series.  It was released on July 27, 2010.  The film stars Bruce Greenwood as Bruce Wayne/Batman, Jensen Ackles as the Red Hood/Jason Todd, John DiMaggio as the Joker, Neil Patrick Harris as Nightwing/Dick Grayson, Jason Isaacs as Ra's al Ghul, and Wade Williams as Black Mask.  The screenplay was written by Judd Winick, who also wrote the "" run in the monthly "Batman" comic.As in the comic, it focuses on Batman dealing with the return of his former apprentice, the second Robin, Jason Todd , who now goes by the moniker of Red Hood, a murderous vigilante and the former alias of Batman's archenemy , The Joker , on whom Jason is trying to exact revenge.

Scarecrow (DC Comics): The Scarecrow (Dr. Jonathan Crane) is a fictional supervillain appearing in American comic books published by DC Comics, commonly as an adversary of the superhero Batman.  The character was created by artist Bob Kane and writer Bill Finger, and first appeared in "World's Finest Comics" #3 (Fall 1941).

Death of the Family: "Death of the Family" is a 23-issue comic book story arc first published by DC Comics in 2012 featuring the fictional superhero Batman and his family of supporting characters.  The arc spans several titles featuring characters of the Batman family including: "Batman", "Batgirl", "Batman and Robin", "Catwoman", "Detective Comics", "Nightwing", "Red Hood and the Outlaws", "Suicide Squad", and "Teen Titans".  The story involves the return of Batman's arch-enemy, the Joker, and his plan to destroy all of the people Batman has come to rely on over the years: the multiple Robins, Batgirl, Catwoman, Alfred Pennyworth, and Commissioner James Gordon.  The title is a reference to the classic Batman story arc "" (1988), in which the Joker murders Jason Todd.

Two-Face: Two-Face (Harvey Dent) is a fictional supervillain appearing in American comic books published by DC Comics, commonly as an adversary of the superhero Batman.  The character was created by Bill Finger and Bob Kane and first appeared in "Detective Comics" #66 (Aug. 1942).  As one of Batman's most enduring enemies, Two-Face belongs to the collective of adversaries that make up Batman's rogues gallery.

Supporting paragraphs: Batman: Under the Red Hood Joker (character)
Answer: Joker