Undertale Wiki

Toby "Radiation" Fox (born October 11, 1991[2]), also known as FwugRadiation, is a music composer and game developer. He developed the critically acclaimed RPG Undertale and produced its soundtrack in 2015. His avatar is the Annoying Dog.


Along with being the main developer and composer of the game, Fox is credited with the conception of the following characters;


Fox originally started out as a forum member at the EarthBound fansite, Starmen.Net, under the alias "Radiation" where he managed the website's PK Hack forum up until 2011.[3] He first entered the public eye with his infamous "EarthBound Halloween Hack", also known as "Press the B Button, Stupid!", which was a submission for Starmen.Net's 2008 Halloween Funfest.[4][5][6]

Fox also produced music for the webcomic Homestuck, after which he would go on to create Undertale which was partially developed in Andrew Hussie's basement.[7][8]


Album Tracks Composed
Midnight Crew: Drawing Dead
(February 4, 2010)
"Liquid Negrocity", "The Ballad of Jack Noir" (Original Version)
Homestuck Vol. 4
(April 13, 2010)
"John Sleeps / Skaian Magicant", "Carefree Victory", "Atomyk Ebonpyre", "Black"
Homestuck Vol. 5
(June 13, 2010)
"Skaian Skirmish", "Savior of the Waking World", "Happy Cat Song!", "Hardchorale", "White", "Octoroon Rangoon", "Lotus Land Story", "Versus", "Dupliblaze COMAGMA", "Moonshatter", "Sunsetter", "Get Up", "Vertical Motion", "Amphibious Subterrain", "Snow Pollen", "Descend"
(July 18, 2010)
"Crustacean", "Showdown", "mIrAcLeS", "The Lemonsnout Turnabout", "Phaze and Blood", "psych0ruins", "Walls Covered In Blood", "dESPERADO ROCKET CHAIRS,", "Death of the Lusii", "Virgin Orb", "The La2t Frontiier", "Skaian Summoning", "Spider's Claw (Bonus)", "Staring (Bonus)", "Keepers (Bonus)"
(August 26, 2010)
"Squiddles the Movie Trailer - The Day the Unicorns Couldn't Play"
The Baby Is You
(October 13, 2010)
"THROGUH SONG", "IM HAVING A BABY, AND THE BABY IS YOU", "bootes", "ROSE PRAGNET (feat. ????)", "the rose rap (feat. von fawn)", "uh oh", "vs. bros", "A BABY IS BORN (feat. artemis251 as luigi, chorus singer, kid, and hella jeff)"
The Felt
(December 2, 2010)
"Humphrey's Lullaby", "English"
Homestuck for the Holidays
(December 25, 2010)
"Carefree Perigee"
Homestuck Vol. 6: Heir Transparent
(January 5, 2011)
"Umbral Ultimatum", "MeGaLoVania", "Gaia Queen", "Wacky Antics", "Nic Cage Song", "A Tender Moment"
(March 14, 2011)
"Karkat's Theme", "Terezi's Theme", "Vriska's Theme", "FIDUSPAWN, GO!", "Darling Kanaya", "Eridan's Theme", "Nautical Nightmare", "Nepeta's Theme", "Killed by BR8K Spider!!!!!!!!", "Catapult Capuchin", "Science Seahorse", "A Fairy Battle", "The Blind Prophet", "AlterniaBound", "You Won A Combat", "Rest A While"
Homestuck Vol. 7: At the Price of Oblivion
(May 31, 2011)
"Terezi Owns", "Rumble at the Rink", "Earthsea Borealis"
The Wanderers
(July 14, 2011)
"Mayor Maynot", "Riches to Ruins Movements I & II", "Tomahawk Head"
Homestuck Vol. 8
(October 25, 2011)
"Love You (Feferi's Theme)", "Davesprite", "Frostbite", "The Lost Child", "Judgement Day", "Penumbra Phantasm" (featured in the third part of "Cascade")
Improvised Touhou Music with Annoying Commentary (November 29, 2011) "Girl's Pretty Dress Dress, Do Your Best Now", "Magical Hopalong Cassidy Station", "An Apple Disaster!"
I Miss You - EarthBound 2012 (January 1, 2012) "Fallen Down", "A New Line", "Megalo Strike Back", "Checkerboard Memories"
coloUrs and mayhem: Universe A
(April 2, 2012)
"~~SIDE 1~~", "~~SIDE 2~~", "~~ADDITIONAL MAYHEM~~"
coloUrs and mayhem: Universe B
(April 13, 2012)
"~~SIDE 1~~", "~~SIDE 2~~", "~~ADDITIONAL MAYHEM~~"
Homestuck Vol. 9
(June 12, 2012)
"Hate You", "ASSAULT", "Stress", "Moonsetter"
Make Music, Throw Music: A Yoshi's Island Tribute (October 26, 2012) "Daffodil Petals", "Terrapin Tower"
(March 14, 2013)
"The Lordling"
Undertale Demo OST
(May 21, 2013)
"Once Upon a Time", "Menu", "Your Best Friend", "Fallen Down", "Ruins", "Anticipation", "Unnecessary Tension", "Enemy Approaching", "Ghost Fight", "Determination", "Home", "Heartache", "End", "Nyeh Heh Heh!", "Home (Music Box)", "Empty House"
UNDERTALE Soundtrack
(September 15, 2015)
"Once Upon a Time", "Start Menu", 'Your Best Friend", "Fallen Down", "Ruins", "Uwa!! So Temperate♫", "Anticipation", "Unnecessary Tension", "Enemy Approaching", "Ghost Fight", "Determination", "Home", "Home (Music Box)", "Heartache", "sans.", "Nyeh Heh Heh!", "Snowy", "Uwa!! So Holiday♫", "Dogbass", "Mysterious Place", "Dogsong", "Snowdin Town", "Shop", "Bonetrousle", "Dating Start!", "Dating Tense!", "Dating Fight!", "Premonition", "Danger Mystery", "Undyne", "Waterfall", "Run!", "Quiet Water", "Memory", "Bird That Carries You Over A Disproportionately Small Gap", "Dummy!", "Pathetic House", "Spooktune", "Spookwave", "Ghouliday", "Chill", "Thundersnail", "Temmie Village", "Tem Shop", "NGAHHH!!", "Spear of Justice", "Ooo", "Alphys", "It's Showtime!", "Metal Crusher", "Another Medium", "Uwa!! So HEATS!!♫", "Stronger Monsters", "Hotel", "Can You Really Call This A Hotel, I Didn't Receive A Mint On My Pillow Or Anything", "Confession", "Live Report", "Death Report", "Spider Dance", "Wrong Enemy !?", "Oh! One True Love", "Oh! Dungeon", "It's Raining Somewhere Else", "CORE Approach", "CORE", "Last Episode!", "Oh My...", "Death by Glamour", "For The Fans", "Long Elevator", "Undertale", "Song That Might Play When You Fight Sans", "The Choice", "Small Shock", "Barrier", "Bergentrückung", "ASGORE", "You Idiot", "Your Best Nightmare", "Finale", "An Ending", "She's Playing Piano", "Here We Are", "Amalgam", "Fallen Down (Reprise)", "Don't Give Up", "Hopes and Dreams", "Burn in Despair!", "SAVE the World", "His Theme", "Final Power", "Reunited", "Menu (Full)", "Respite", "Bring It In, Guys!", "Last Goodbye", "But the Earth Refused to Die", "Battle Against a True Hero", "Power of "NEO"", "MEGALOVANIA", "Good Night"
[S] Collide.
(April 6, 2016)
"Oppa Toby Style"
Hiveswap Act 1 OST
(September 14, 2017)
(November 1, 2018)
"ANOTHER HIM", "Beginning ", "School ", "Susie ", "The Door ", "Cliffs ", "The Chase ", "The Legend ", "Lancer ", "Rude Buster ", "Empty Town ", "Weird Birds ", "Field of Hopes and Dreams ", "Lantern ", "I'm Very Bad ", "Checker Dance ", "Quiet Autumn ", "Scarlet Forest ", "Thrash Machine ", "Vs. Lancer ", "Basement ", "Imminent Death ", "Vs. Susie ", "Card Castle ", "Rouxls Kaard ", "April 2012 ", "Hip Shop ", "Gallery ", "Chaos King ", "Darkness Falls ", "The Circus ", "THE WORLD REVOLVING ", "Friendship ", "THE HOLY ", "Your Power ", "A Town Called Hometown ", "You Can Always Come Home ", "Before the Story ",
Hiveswap Friendsim
(December 15, 2018)

"CLOWNFUCKER", " yall know i just do the music right"

YIIK: A Postmodern RPG
(January 17, 2019)

"Into the Mind (Toby Fox)"

Little Town Hero OST
(October 16, 2019)
"3 Kids",
Super Smash Bros. Ultimate OST
(September 4, 2019)
Kiwi Blitz "Kiwi Blast"
Pokémon Sword and Shield OST
(November 15, 2019)
"Battle Tower"
Dweller's Empty Path OST
(July 10, 2020)
"Dweller's Empty Path (Trailer Theme)", "Somewhere in a Forest", "Yoki's House", "Leaves Fill The Path", "Small Village", "Aimottle's House", "Officeish Space", "Beneath the Towering Castle", "Buy Something Will You ...Can't", "Inside the Castle", "Always this graveyard is gloomy", "Cool Cat", "Underground Path", "Dragon Temple", "Breath of the Dragon", "Forgotten Memories", "Flying Through A Starry Sky", "Frozen Palace", "Be Brave!", "Breezy Palace", "Temmie's Room"
HIVESWAP: ACT 2 Original Soundtrack

(November 26, 2020)

"Above Sea Level", "Studio Space", "Raw Honey", "Ticket to Ride: Quadrant Confusion", "Ticket to Ride: Trial Variation", "Ticket to Ride: The Other Half", "Conductor's Cabin"

(December 25, 2020)

U.U.F.O (July 11, 2021) "Myths You Forgot"

(September 17, 2021)

"Faint Glow", "Girl Next Door", "My Castle Town", "Ohhhhohohoho!", "Queen", "A CYBER'S WORLD?", "A Simple Diversion", "Almost To The Guys!", "Cool Beat", "When I Get Mad I Dance Like This", "Cyber Battle (Solo)", "When I Get Happy I Dance Like This", "Sound Studio", "Berdly", "Smart Race", "Faint Courage (Game Over)", "WELCOME TO THE CITY", "Mini Studio", "Holiday Studio", "Cool Mixtape", "HEY EVERY !", "Spamton", "NOW'S YOUR CHANCE TO BE A", "Elegant Entrance", "Bluebird of Misfortune", "Pandora Palace", "KEYGEN", "Acid Tunnel of Love", "It's Pronounced "Rules"", "Lost Girl", "Ferris Wheel", "Attack of the Killer Queen", "Giga Size", "Powers Combined", "Knock You Down !!", "The Dark Truth", "Digital Roots", "Deal Gone Wrong", "BIG SHOT", "A Real Boy!", "Dialtone", "sans." "Chill Jailbreak Alarm To Study And Relax To", "You Can Always Come Home", "Until Next Time", "Before The Story"



  • Toby Fox has visited this wiki's Dog Residue article[9] and commented on a piece of misinformation on the Papyrus article claiming that the character was inspired by Octopimp.[10][11]
  • Toby Fox is embarrassed by his Halloween Hack and has dubbed it "bad ROM hack with swears".[12][13]
  • Although Toby Fox's official website's content was replaced with a link to the UNDERTALE website, a part of it with music composed by Toby still exists. For some reason, the name "musics" in the URL is misspelled "msuics".
  • The program Toby Fox used to make the music of Undertale was FL Studio. According to music tags in the beta version of Stronger Monsters from his website and the tracks he made for Temmie Chang's RPG, he uses FL Studio 10.[14]
  • The copyright on Undertale and Deltarune is registered to "Robert F. Fox,"[15] and Toby's Halloween Hack was credited to Robert "Toby" Fox,[16] suggesting that Toby's birth name might be Robert Fox.
  • Toby Fox and Temmie Chang animated a commercial for Kenny Omega when he went to go fight in Japan. The commercial uses music used in Undertale and is stylised as Undertale's gameplay.[17]
  • On April Fools' Day of 2023, Toby Fox "accidentally" sent a picture of himself covered in a large amount of foam to some of the "TRUCK FREAK" subscribers to the Undertale/Deltarune newsletter.[18]
    • People subscribed to the "Foam Shower" tier also received several other images, with the previous image of Toby photoshopped into them.[19]


  1. If you're going to post pictures of me, just make it this one. - Toby Fox (@tobyfox) on Twitter, January 31, 2016.
  2. 2.0 2.1 Art club day. It's easy to remember because I made it right before my birthday. - Toby Fox (@tobyfox) on Twitter, October 10, 2017.
  3. https://forum.starmen.net/members/473
  4. "Okay, finally finished. After wayyy over 140 hours (I spent hours every day since 9-12, yeah some days I didn't do stuff but some days I was up until 12 since after school) I have finished my hack. Eeeeek." - Toby Fox. November 1, 2008. Starmen.Net.
  5. "This is the censored version of my hack. Technically they are exactly the same except for some swears near the end, but if you don't mind or are judging, I highly suggest you play the version provided at the following URL: http://forum.starmen.net/forum_attachments/0007/0301/radiationhalloweenhack.zip Otherwise, this hack is NOT appropriate for you." - Toby Fox. November 6, 2008. Starmen.Net. Halloween Funfest 2008.
  6. Today is Halloween, so it's a good time to post some Halloweeny stuff! So my obvious choice was Radiation's Halloween hack of EarthBound from last year. - EarthBound Halloween Hack! (October 31, 2009.) EarthBound Central.
  7. @andrewhussie THANKS ANDREW!!! and i said it before but thanks for letting me start making undertale in your basement - Toby Fox (@tobyfox) on Twitter, September 15, 2015. Archived on May 04, 2016.
  8. "Actually, yes, he literally spent a period of time developing Undertale in my basement. I have always assumed this is why he titled the game as such." - Andrew Hussie. December 25, 2015. Kickstarter.
  9. about me - @FwugRadiation on Twitter, November 02, 2015. [deleted]
  10. uhhhhhhhh........ no LOL? deconfirmed? - @FwugRadiation on Twitter, November 02, 2015. Archived on November 16, 2015.
  11. "Going off the information given, I was banned from the Undertale Wiki yesterday (Nov. 2nd, 2015) for adding false information to page for the character Papyrus, where I added to the Trivia section that he was based off the YouTube Octopimp. Alongside the claim, I provided a link to a now-defunct live stream for the YouTube channel Game Grumps. However, yesterday, the creator of Undertale, Toby Fox, said on Twitter that this wasn't true, with Octopimp later following suit and also saying it was false. I was later banned from Undertale Wiki for adding said false information, with the accusation from replies to Toby's tweet that I was a troll." - GamingFanatic. November 4, 2015. Wikia.
  12. Fan theories are fun but I feel embarrassed whenever someone calls attention to something I did when I was 16 - Toby Fox (@tobyfox) on Twitter, February 09, 2016. Archived on June 29, 2016.
  13. I guess I should just accept "bad rom hack with swears" as part of my eternal legacy - Toby Fox (@tobyfox) on Twitter, February 09, 2016. Archived on June 29, 2016.
  14. Undertale FAQ
  15. United States Copyright Office
  16. Toby's old website on Halloween Hack
  17. “Kenny's Quest" - YouTube
  18. "Due to a glitch in our mailing system, it appears that around 1,000 of you have been erroneously subscribed to the "Foam Shower" tier. Affected subscribers were sent a photo of Toby Fox in swim trunks covered in a large amount of foam." - Undertale/Deltarune Newsletter
  19. "We apologize again. It seems that those in the Foam Shower tier continued to receive various images unintentionally." - Undertale/Deltarune Newsletter

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