Question: Which character created by Brian K. Vaughan and Adrian Alphona has control of a vehicle in the form of a large frog?

Context paragraphs:
Pride &amp; Joy (comics): "Pride & Joy" is a six-issue story arc from the comic book series "Runaways" (vol.  1), published in issues one through six in 2003 by Marvel Comics' imprint Tsunami, which was created to attract young readers.  It was written by Brian K. Vaughan and illustrated by Adrian Alphona.  While it was initially intended to be a six-part miniseries, the popularity of "Pride & Joy" and new ideas from writer Vaughan allowed "Runaways" to grow into a regular monthly Marvel title.  "Pride & Joy" has subsequently won several comics awards, including the 2006 Harvey Award for Best Continuing or Limited Series.

Leapfrog (comics): The Leapfrog is a fictional vehicle appearing in American comic books published by Marvel Comics.  The Leapfrog is the personal mode of transport for the superhero team Runaways.  The ship takes on the form of a large frog.  Originally created by Janet Stein and Victor Stein, the Leapfrog was used by the Pride when they had to perform their Rite of Thunder for the Gibborim.  After the Pride was destroyed by the Gibborim, control of the Leapfrog rested with Chase Stein and has since been used as the primary mode of transportation for the Runaways.  The Leapfrog doesn't actually fly; it "jumps" forward to move.

Chase Stein: Chase Stein (also known as Talkback), is a fictional character, a superhero in the Marvel Comics "Runaways".  He was created by author Brian K. Vaughan & artist Adrian Alphona, and debuted in "Runaways" vol.  1 #1 with most of the other main characters.  Like every member of the original Runaways, he is the son of evil villains with special abilities; in Chase's case, mad scientists.  Chase is often regarded as the "wild card" in the series, due to his often changing role in the group, from being the getaway guy and technical guru to the "loose cannon" after he departed the group for a short while.  However, despite his rule-breaking persona, Chase is fiercely loyal to his friends and remains a valued member of the team.  Chase is the eldest of the Runaways at age 18.  Chase shares a psychic and empathic link with deinonychus Old Lace, granting him the ability to command the dinosaur to do his bidding and also possesses the Fistigons, the world's most powerful gauntlets.

Loners (comics): Loners (originally named Excelsior) is a spin-off mini-series of comic books from Marvel Comics, first appearing in the pages of "Runaways".  It consists of a Los Angeles-based support group for former teenage superheroes from New York, founded by Turbo of the New Warriors, and Phil Urich, the heroic former Green Goblin.  Their goals are initially stated to be to help fellow teenage superheroes to adjust to normal lives while coping with their powers, and to dissuade other superpowered teenagers from becoming heroes, but these goals are discarded in their own miniseries in favor of the group apparently wanting to avoid using their powers for any reason, even if that means abandoning helpless victims of crime to their fate.  Although all the characters were created by different authors and artists, the team itself was created by Brian K. Vaughan and Adrian Alphona, with other characters (Spider-Woman, Hollow, and Red Ronin) added to the cast during the events of the 2007 miniseries.

Xavin: Xavin is a fictional superhero in the Marvel Comics "Runaways".  They are a Super-Skrull in training, created by author Brian K. Vaughan & artist Adrian Alphona, and debuted in "Runaways" vol.  2 #7.  Although Alphona was the series' artist at the time, artist Takeshi Miyazawa first drew the character on print.  Xavin had first appeared to the Runaways, taking on the form of a black male, but changed into a black female just for the sake of Karolina Dean, a lesbian whom they were to marry.  Xavin is often seen as a male, simply to be "intimidating".  Xavin, often called "Xav" for short, is known for their obtuse and warlike personality.  They had originally found it hard to fit in with the Runaways due in part to their constant gender switching and unfamiliarity with Earth values and norms, though through proving their loyalty to the group, found acceptance.  They are the child of the Skrull Prince De'zean.

Gertrude Yorkes: Gertrude Yorkes (self-referred to as Arsenic), is a fictional superheroine in the Marvel Comics "Runaways".  She was created by author Brian K. Vaughan & artist Adrian Alphona, and debuted in "Runaways" #1 with most of the other main characters.  Like every member of the original Runaways, she is the daughter of evil villains with special abilities; in Gert's case, time-travellers.  Gertrude, often called "Gert" for short, is often regarded as the most "book-smart" of the Runaways yet also the most sarcastic and cynical.  She has socialist leanings and is ethnically Jewish but spiritually agnostic.  Gert is known for her sarcastic one-liners, glasses, and purple-dyed hair.  She stands at a rough height of 5'1" and weighs 125 lb .

Runaways (comics): Runaways is a superhero comic book series published by Marvel Comics.  The series features a group of teenagers who discover that their parents are part of an evil crime organization known as "The Pride".  Created by Brian K. Vaughan and Adrian Alphona, the series debuted in July 2003 as part of Marvel Comics' "Tsunami" imprint.  The series was canceled in September 2004 at issue eighteen, but due to high numbers of trade collection sales, Marvel revived the series in February 2005.

Nico Minoru: Nico Minoru (briefly known as Sister Grimm), is a fictional superheroine appearing in American comic books published by Marvel Comics.  She first appeared in the Marvel Comics "Runaways".  Created in 2003 by writer Brian K. Vaughan and artist Adrian Alphona, the character debuted in "Runaways" vol.  1 #1 (July 2003).  Like every member of the original Runaways, Nico is the daughter of the super-powered villains calling themselves "the Pride"; in her case, she is the daughter of dark wizards.  Upon finding out, Nico runs away with the rest of the runaways but later discovers that she inherited her parents' magical aptitude.  Whenever Nico bleeds, a powerful staff emerges from her chest, allowing Nico to bend magic.

List of Runaways story arcs: "Runaways" is an American comic book series created by Brian K. Vaughan and Adrian Alphona for Marvel Comics.  The series debuted in April 2003.  It has covered 13 story arcs, and is currently in its fourteenth.  "Runaways" has frequently been collected in digest-sized books, which led to booming sales.  Series creator Vaughan wrote the entire first volume and most of the second, which was continued and ended by Joss Whedon.  Terry Moore, creator of "Strangers in Paradise" currently runs the series.

Gibborim (comics): The Gibborim are a group of fictional characters appearing in comic book series, "Runaways", published by Marvel Comics.  They were created by author Brian K. Vaughan and artist Adrian Alphona.  Debuting in "Runaways" #13 (March 2003), in a flashback sequence, the Gibborim are the last known survivors of an ancient race of six-fingered giants who ruled Earth before humanity's dawn, called "elder gods" by Witchfire, and possibly servants of the Judeo-Christian God.  Their apparent goal is to wipe the Earth clean of all humanity and reshape the realm to create a new Eden to make their "holy Father" proud.  They were the evil benefactors of the Pride.  Averaging a rough height of 100 ft , the Gibborim despise all humans.

Supporting paragraphs: Leapfrog (comics) Chase Stein
Answer: Chase Stein