Toby Fox

Fox then moved on to composing music, including for Andrew Hussie's 2009 webcomic Homestuck. In 2015, Fox created Undertale, which became a breakout hit and pop-culture phenomenon. It has received nominations for a British Academy Game Award, three Game Awards, and three D.I.C.E. Awards.[32] Following the success of Undertale, Fox went on to compose music for several other indie games, as well as contributing to the soundtracks of Super Smash Bros. Ultimate and the Pokémon video games. From 2018 onwards, Fox began releasing Chapters of Deltarune, an episodic video game set in a parallel universe to Undertale; the game has received critical acclaim.

Toby Fox studied at Northeastern University and Manchester Central High School. The recorded working language is English and Japanese. Off is recorded as an influence. Residence is recorded at Boston and Manchester. Works named in the authority record are Undertale and Homestuck.

• Name — Toby Fox • Other Names — * Radiation • FwugRadiation • Birth Name — Robert F. Fox • Born — 11 October 1991 • Birthplace — Manchester, New Hampshire, US • Occupation — * Video game developer • composer • Years Active — 2008–present • Education — Northeastern University (BS) • Works — * Undertale • Deltarune

Robert F. Fox was born on October 11, 1991,[2] in Manchester, New Hampshire, the third of four brothers.[4] Fox discovered the role-playing video game EarthBound when he was four years old after it was gifted to one of his older brothers for "Christmas or his birthday", and credited the game with helping him learn how to read.[5] During church service around age five, he often drew fictional stage layouts based on the Mega Man X series.[6] While Fox attended elementary school, his brothers told him about RPG Maker 2000—a program used to develop RPGs—and they began creating games together using it, including Toby's Adventure, Fox's first game.[7] Fox learned about the Touhou Project franchise through a free games website at age 10, and played the demo versions of Embodiment of Scarlet Devil and Perfect Cherry Blossom.[8] • Illustration — Fox playing piano in 2012 Fox's interest in EarthBound was furthered at age 11 after discovering a fansite for the game, Starmen.net, which motivated him to create games to impress the site's members. Using the ROM hack editor PK Hack, which he considered his "entrance into [the] community", Fox created his first hack in middle school.[9] Under the username Radiation, he released EarthBound Halloween Hack in 2008 as part of a ROM hacking competition on Starmen.net, additionally composing the song "Megalovania" for the hack's soundtrack.[10] When Fox was disallowed by his parents from attending a yearly Starmen.net forum meetup due to his age, the forum's founder Reid Young advised Fox to threaten to "smoke a cigarette" if he wasn't allowed to attend, which ultimately worked.[11] Fox additionally discovered the English fan translation of the RPG OFF through the forum.[12] Primarily a self-taught musician, Fox began relearning the piano during middle school to play video game music he knew by ear, having previously taken lessons in second grade; he also played the trumpet through high school.[13] Fox recalled to Touhou Project creator ZUN that he had received a standing ovation following a piano rendition of "Necrofantasia" from Perfect Cherry Blossom during a high school summer camp gathering. As a senior, he began creating piano covers of music from the webcomic Homestuck, gaining recognition from its creator Andrew Hussie, and later became the music team's production coordinator.[14] Fox is a graduate of Northeastern University.[15]

• Illustration — The logo for Undertale During his third year of university, Fox was inspired to create Undertale in December 2012 after reading a Wikipedia article about the array data structure, later using it to program text and battle systems for an RPG.[16] Development on Undertale started during a break from his classes in 2013, and Fox prioritized creating the game's battle system first.[18] Undertale initial development began out of Hussie's basement while Fox simultaneously worked on the Homestuck soundtrack. Fox discovered Temmie Chang's blog while looking for an artist, and despite having never talked to her before, Fox asked Chang if she wanted to create a game together, to which she agreed. Fox additionally began writing down design notes and sketching character designs in his school notebook.[19] After completing a downloadable demo by June 2013, Fox created a Kickstarter campaign for Undertale that month with a goal of $5,000, slating the game for a Summer 2014 release. The campaign ultimately raised over ten times that amount, totaling $51,124 from 2,398 people.[20] Though Fox was initially "unsure if it was humanly possible to create [Undertale] before making the demo," he considerably expanded the game's scope following the demo's release. Fox used the Kickstarter's proceeds to continue working on the game until its release in September 2015. Undertale was developed almost entirely by Fox himself, except for some art assets.[21] Undertale released on September 15, 2015,[22] to widespread critical acclaim, and has been ranked by numerous publications as one of the best video games of all time. Undertale soundtrack has additionally been named one of the best video game soundtracks. Undertale gained immediate popularity on Steam, selling over 500 thousand copies within three months, doubling again to a million two months later. In GameFAQs's "Best. Game. Ever." poll that December, Undertale won against The Legend of Zelda: Ocarina of Time, the incumbent game from a similar 2009 poll, in a final vote of 156,000 participants.[31] The game was nominated for various other accolades at game award ceremonies through the following year, including at the D.I.C.E. Awards, the Game Awards, and the Game Developers Choice Awards.[34] The rapid rise of the Undertale fandom's popularity and its behavior towards those who disliked the game led Fox to comment about the matter on Twitter in January 2016, where he stated, "It's OK if people don't like the game. I don't care," further hoping the game would have an "overall good effect on the world".[36] In May 2016, internet personality MatPat gifted Pope Francis a Steam key of Undertale during a meeting between the Pope and numerous other YouTubers.[37] Before Undertale first anniversary, Fox made a retrospective post on Tumblr describing his feelings about the game's success and the stress the attention brought him, further referring to Undertale as "about an 8/10, niche RPG game."[39] In November 2017, Fox was included on Forbes 2018 list of 30 Under 30 in Games for his work on Undertale.[40]

• Illustration — The logo for Deltarune Fox initially conceived of the idea for his game Deltarune in a fever dream in 2011, with an initial version being created in 2012 before being abandoned.[41] On October 30, 2018, Fox posted a request for fans of Undertale to check its official Twitter account in 24 hours. The following day, Fox released the first chapter of Deltarune for free under the guise of a "survey".[42] Deltarune takes place in a parallel universe to the setting of Undertale, with Fox describing it as being "more enjoyable" to those that had completed it.[44] At the time, Fox stated that he did not wish to spend longer than seven years on the project; he expressed interest in assembling a team to aid development, stating that without one he had "absolutely no estimation of its completion".[45] After Deltarune had been playable for several months, Fox stated he had hope he would complete its remainder, saying: "Slowly I'm writing and drawing it all out."[47] He stated that he had already written about 50 songs past Chapter 1.[48] On September 17, 2021, Fox released the second chapter of Deltarune for free since "the world has been really tough for everybody recently", referring to the struggles of the COVID-19 pandemic. He released the next two chapters, 3 and 4, bundled in with the first two as a paid game on June 4, 2025;[49] future chapters will be added to it as free updates for owners of the paid version.[53] On June 24, 2026, Chapter 5 was released, and Chapter 6 is projected to release in 2027.[54] Deltarune is set to have a total of seven chapters.[56]

Outside of Undertale and Deltarune, Fox has worked on other projects. The video game magazine A Profound Waste of Time has featured Fox as a contributor.[57] The success of Undertale, especially in Japan, afforded Fox the opportunity to meet Super Smash Bros. creator Masahiro Sakurai.[58] In September 2019, Sans, a character from Undertale, was later included in Super Smash Bros. Ultimate as a Mii costume available through downloadable content, along with an instrumental composition "Megalovania", for which Fox provided a new arrangement.[59]

Fox has composed music for the 2017 Homestuck video game Hiveswap, Undertale artist Temmie Chang's short narrative game Escaped Chasm,[61] and Game Freak's 2019 role-playing game Little Town Hero, the last of which was arranged by Pokémon composer Hitomi Sato. He also composed a track for Pokémon Sword and Shield,[62] and multiple tracks for Pokémon Scarlet and Violet.[63] He also remixed Ed Sheeran's "Celestial" for Scarlet and Violets expansion The Indigo Disk.[65] In 2024, he partnered with Japanese game developer ZUN for the Touhou Danmaku Kagura Phantasia Lost downloadable content, which included a track that combined the Touhou song "U.N - Owen Was Her?" with Undyne the Undying's boss battle theme "Battle Against a True Hero" from Undertale.[66] Fox has done voice acting work for multiple television and web series. In 2023, Fox had his voice acting debut in the animated television series We Baby Bears. He plays a skeleton named Jared in the episode "Polly's New Crew".[67] Fox stated that it had "been a dream of [his] to be a voice actor in cartoons".[68] In 2025, Fox voiced John Egbert in the Homestuck animated pilot.[69]

During an Undertale speedrun at the Games Done Quick event AGDQ 2017, Fox made a $10,000 donation.[70] Undertale has been part of several Humble Bundles, collections of games sold to support charity, including two that donated all proceeds to coronavirus relief during the COVID-19 pandemic, raising $6.5 million in 2020 and $1.1 million in 2021.[71] To commemorate Undertale 7th anniversary in 2022, Fox held the "Spamton Sweepstakes" charity auction on September 17, in support of Child's Play and Pakistan Children Relief, through Deltarune website.[73] The event ultimately raised $322,805.68.[74] Following a 2024 copyright dispute between the team of Undertale fan game Undertale Yellow and Materia Collective's CEO Sebastian Wolff over the use of Fox's music in the game, Fox donated $20,000 to AbleGamers as a token of apology.[75] For Undertale 10th anniversary, Fangamer and Fox held a two-day livestream in support of Doctors Without Borders on September 21 and 22, 2025, holding auctions for collectables and featuring new in-game content exclusive to the stream.[76] This livestream raised $361,407 across both days.[78]

• Illustration — Fox often hides his face, using the Annoying Dog (face shown) as a self-insert Fox has been described as "a very private person," and has a relatively restrained presence on social media. He only does interviews occasionally.[82] The Annoying Dog character in Undertale (pictured) is Fox's self-insert that he uses as an author surrogate. In most filmed interviews, he uses a Annoying Dog puppet to hide his face.[83] Fox has lived in Boston, Massachusetts for a majority of his life.[84] He has chronic wrist and hand pain that regularly disables him from programming and composing, and often relies on speech-to-text software as his computer input method. In September 2020, Fox cited a flare-up of this pain as a factor in the delayed development of Deltarune.[85][86] Fox can speak Japanese and has a pet cat called Kikky.[87]

• Year — Title — Director — Composer — Writer — Platforms • 2006 — Arn's Winter Quest — Super Nintendo (ROM hack) • 2008 — EarthBound Halloween Hack — Super Nintendo (ROM hack) • 2015 — Undertale — Windows, macOS, Linux, PlayStation 4, PlayStation Vita, Nintendo Switch, Xbox One • 2016 — Rose of Winter — Windows • 2017 — Hiveswap: Act 1 — Windows, macOS, Linux • 2018 — Deltarune Chapter 1 — Windows, macOS, PlayStation 4, Nintendo Switch, PlayStation 5, Nintendo Switch 2 • 2019 — Escaped Chasm — Windows • Little Town Hero — Windows, PlayStation 4, Nintendo Switch, Xbox One • 2020 — Dweller's Empty Path — Windows • Hiveswap: Act 2 — Windows, macOS, Linux • 2021 — Deltarune Chapter 2 — Windows, macOS, PlayStation 4, Nintendo Switch, PlayStation 5, Nintendo Switch 2 • 2022 — Pokémon Scarlet and Violet — Nintendo Switch • 2025 — Deltarune Chapters 3+4 — Windows, macOS, PlayStation 4, Nintendo Switch, PlayStation 5, Nintendo Switch 2 • Off (remaster) — Windows, Nintendo Switch • 2026 — Deltarune Chapter 5 — Windows, macOS, PlayStation 4, Nintendo Switch, PlayStation 5, Nintendo Switch 2

• Year — Title — Director — Composer — Writer — Platforms • Hiveswap: Act 3 — Windows • Deltarune Chapter 6 — Windows, macOS, PlayStation 4, Nintendo Switch, PlayStation 5, Nintendo Switch 2 • Deltarune Chapter 7 — Windows, macOS, PlayStation 4, Nintendo Switch, PlayStation 5, Nintendo Switch 2

• Hiveswap Friendsim (2018) • YIIK: A Postmodern RPG (2019)[106] • Super Smash Bros. Ultimate (2019) – DLC only • Pesterquest (2019) • Pokémon Sword and Shield (2019) • Omori (2020) – jukebox music only[109] • beatmania IIDX 30 Resident (2022)[110] • Mr. Saitou (2023) • Touhou Danmaku Kagura Phantasia Lost (2024)[112] • Fields of Mistria (2024)[113] • Chunithm Verse (2024)

• Year — Media type — Media title — Role — Notes • 2009–2016 — Webcomic — Homestuck — Composer • 2010 — Album — The Baby is You — Writer, composer, vocalist — Album made for Homestuck • 2012 — Album — I Miss You - EarthBound 2012 — Composer • 2012 — Website — tane.us — Guest arrangement — Metronomy - Black Eye Burnt Thumb (Toby "Radiation" Fox CHIP MIX) • 2018 — Album — Pray — Guest composer, lyricist and vocalist • Video game — Black Bird — Game testing • 2020 — Comic — Hobonichi Mother Project "Pollyanna" comic — Contributor • Music video — Chip Tanaka/Hammerhead Shark Song — Director/animator (music video) • 2021 — Video game — Get in the Car, Loser! — Credited for providing guest items and stories • Song — "Myths You Forgot" — Featured artist — In collaboration with Camellia • 2022 — Song — "Skies Forever Blue" — Composer, writer — In collaboration with Itoki Hana • Commercial — Pocari Sweat — Composer — In collaboration with PUNPEE and imase • 2023 — Song — "The Greatest Living Show" — Composer, writer — In collaboration with Itoki Hana • Song — "Prelude" — Composer — In collaboration with bo en • Animated television series — We Baby Bears — Voice actor (2 episodes) • Downloadable content — Pokémon Scarlet and Violet: The Hidden Treasure of Area Zero — Composer — Remix of Ed Sheeran's "Celestial" • 2024 — Song — "Fallen Wing" — Composer — As a guest composer for Hololive VTuber Amane Kanata's Unknown DIVA album, with Camellia • Song — "Dead Ma'am's Chest" — Composer — In collaboration with Hololive VTuber Houshou Marine and Camellia • 2025 — Web series — Homestuck: The Animated Pilot — Composer, Executive Producer, voice actor (John Egbert) — Credited as Toby "Radiation" Fox • 2026 — Web series — Gameoverse — Special thanks

Toby Fox was recorded at birth as Robert F. He also worked under the names Toby Fox, Radiation and FwugRadiation. The authorities additionally record the headings Radiation, Robert F. Fox, Robert Fox and FwugRadiation. His recorded languages were English and Japanese.

Toby Fox is recorded with the occupation video game developer. Recorded with the occupation graphic designer. Recorded with the occupation screenwriter. Recorded with the occupation composer. Recorded as composer, video game developer, video game designer, graphic designer and screenwriter. Recorded at birth as Robert F.