Derek Yu | Code Like It's 198x

Derek Yu is best known for Spelunky, the free 2008 PC game that rebuilt its caves every time the player went in. Wireframe wrote in 2020 that “hundreds of rogue-lites followed suit”. Edge, which called the game “Derek Yu’s masterpiece”, introduced him in 2012 as a “developer, illustrator and comic artist” who “may seem to have a split focus”, though not, it added, in the quality of his games. Before Spelunky he made freeware games with friends, took over the website and forum where much of the independent games scene met, and co-created an award-winning underwater adventure. After it he spent eight years with five other developers on UFO 50, fifty games credited to a 1980s games company that never existed.

Fast facts

Born: 1982, in Pasadena, California.
Early games: Diabolika (1999); Eternal Daughter (2002), made with a friend; I’m O.K. – A Murder Simulator (2006).
TIGSource: took over the independent games blog from its founder, Jordan Magnuson, and ran it and its forums.
Aquaria (2007): co-created with Alec Holowka as Bit Blot; Seumas McNally Grand Prize at the 2007 Independent Games Festival.
Mossmouth: founded in 2009 “as a one-man studio to release Spelunky”.
Spelunky: freeware for Windows, December 2008; rebuilt for the Xbox 360, released on 4 July 2012.
Spelunky 2: with BlitWorks, September 2020.
Book: Spelunky, Boss Fight Books, 2016.
UFO 50: with Jon Perry, Eirik Suhrke, Ojiro Fumoto, Paul Hubans and Tyriq Plummer, September 2024.

Freeware years

Yu was giving games away by 1999, when his first Diabolika appeared. The biggest of his early projects was Eternal Daughter, a freeware platform game of 2002 that he made with a friend, Jon. On his own site he calls it “pure Metroidvania, with a dash of Popful Mail for flavor”, an epic that “took myself and my friend Jon two years to make and nearly destroyed our immortal souls”. The Metroidvania entry explains the kind of game he meant. Smaller freeware games followed, among them Diabolika II and Mean Cuisine (2003) and Quibble Race (2004).

In 2006 he made I’m O.K. – A Murder Simulator, a satirical run-and-gun game, with three other developers. It answered the anti-games campaigner Jack Thompson, who had offered money to charity if developers would make a game in which video game makers were killed. One of Yu’s collaborators was Alec Holowka. “I met Alec when he contacted me about working on I’m O.K.,” Yu said later. “At one point, he showed me a prototype for Aquaria, and I thought it was cool!”

TIGSource

TIGSource, The Independent Gaming Source, was not Yu’s creation. “TIGSource was started by Jordan Magnusson as a small blog to review indie games and interview their creators,” he explained in 2011. “I was interviewed by Jordan for the site shortly before he announced that he was going to close it down for personal reasons. I offered to take it over from him and that’s how I got involved in the indie games community.”

By 2006 Retro Gamer, answering a reader’s letter, wished it had room for “the many cool releases mentioned daily on www.tigsource.com”. The site’s forums became a place where games were made in public. Lucas Pope kept a public development log for Papers, Please on the TIGSource forums from late 2012, and Edge reported that its members persuaded him to keep the pixel art when he thought of switching to a smoother look. Andrew Stewart, the developer of Mable And The Wood, told Wireframe he had met all but one of his collaborators there.

Aquaria

Yu and Holowka formed Bit Blot to make Aquaria, an underwater exploration game. “Our original idea was to create an action RPG that was populated with all kinds of NPCs that you could interact with,” Yu said. “Over time, we scaled back and focused on telling the story through monologues that played as you explored the world.” In 2007 it won the Seumas McNally Grand Prize, the main award of the Independent Games Festival, which Edge reported as going to “an accomplished and imaginative undersea adventure”. Five years later Yu told Edge that Aquaria had “really evolved and changed a lot over its development”, and that the game he made next was the opposite.

Spelunky

“I was working on some simple platformer and roguelike prototypes,” Yu told Retro Gamer, “when it occurred to me that a randomised platformer might be fun.” Spelunky, made with Game Maker and given away in December 2008, sent a small explorer through caves that were never the same twice, and ended every run for good when he died. “Spelunky’s a game where it worked from the beginning,” he told Edge. “I started with this really simple randomly generated level and just added things.” Building it, he said, “I felt like a mad scientist.” The game’s own entry tells its story in full.

In 2009 he set up Mossmouth, “as a one-man studio to release Spelunky”, in his words. With the programmer Andy Hull and the composer Eirik Suhrke he rebuilt the game for Microsoft’s Xbox Live Arcade, where it came out on 4 July 2012 under its original name. Edge had previewed it as Spelunky HD. “Even with the basic concept left largely untouched it was still a monstrous amount of work for three people,” Yu said. He replaced his own pixel art with a painted style and added play for up to four people.

What he wanted from games, he told Retro Gamer, was the feeling of old ones, which “tend to treat discovery as a sacred part of play”. He had little time for games that notice a player is stuck and offer an easier setting. “Really, comfort is the last thing I want out of a videogame.”

After Spelunky

In 2014 Yu and Jon Perry designed a card game, Time Barons. In 2016 Boss Fight Books, which publishes a series of books each about a single game, brought out Yu’s own account of making Spelunky. Spelunky 2, made by Mossmouth with BlitWorks, came out for the PlayStation 4 and the PC in September 2020. Wireframe, reviewing it, called it “Derek Yu’s long-gestated sequel” and “a bullish, uncompromising love letter to its masochistic fan base”.

The long gestation had company. UFO 50 was already in Wireframe’s list of games to look forward to in November 2018, with a release date of “TBA 2019”. It is a collection of fifty complete games that Yu, Perry, Suhrke, Ojiro Fumoto, Paul Hubans and Tyriq Plummer wrote as if they came from “a fictional 80s video game company that was obscure but ahead of its time”. Every game keeps to the same imaginary 8-bit hardware, with a fixed 32-colour palette. Yu told Wireframe that the team had looked at machines other than the NES: “The vibe we were going for is slightly off the beaten path.” They also left out the habits of the period that nobody misses. “I imagine the majority of people who grew up with 8-bit gaming don’t miss taking cheap hits or having to rescue a princess in every other title,” he said. “Throwing out those tired tropes and traditions just makes the games better.” UFO 50 came out on Steam on 18 September 2024 and on the Nintendo Switch on 7 August 2025. Two of its games are remakes of Yu’s own early freeware.

Sources

Edge issue 175, May 2007: Independent Games Festival awards (the Seumas McNally Grand Prize to Aquaria).
Edge issue 244, September 2012, pp. 86–91: Spelunky review (“Derek Yu’s masterpiece”) and interview with Derek Yu (“developer, illustrator and comic artist”; Aquaria; how Spelunky began; “a mad scientist”).
Edge issue 237, February 2012: Spelunky HD preview, as cited in the Spelunky entry.
Edge issue 262, January 2014: Papers, Please feature (Lucas Pope’s development log on the TIGSource forums).
“A moment with… Derek Yu”, Retro Gamer issue 107, October 2012, p. 14: the randomised platformer; discovery and comfort; three people on the Xbox version; the painted art.
Retro Gamer issue 33, 2006: letters page (“the many cool releases mentioned daily on www.tigsource.com”).
Wireframe issue 3, November 2018: UFO 50 preview (“TBA 2019”).
Alan Wen, “Modern games, retro constraints”, Wireframe issue 12, April 2019, pp. 44–45: UFO 50, its fictional 1980s maker and 32-colour palette; Yu’s comments.
Wireframe issue 17, June 2019: Andrew Stewart on Mable And The Wood and the TIGSource forums.
Wireframe issue 32, February 2020: “hundreds of rogue-lites followed suit”, as cited in the permadeath entry.
Jon Bailes, Spelunky 2 review, Wireframe issue 44, October 2020, p. 98.
Todd B., “Developer Interview: Derek Yu on Aquaria, TIGSource and Indie Development”, Linux Game Consortium, 5 September 2011 (web, secondary): TIGSource and Jordan Magnuson; meeting Holowka through I’m O.K.; Aquaria’s design. https://linuxgameconsortium.com/developer-interview-derek-yu-on-aquaria-tigsource-and/
Derek Yu, “Games”, derekyu.com (web, secondary; his own site): Eternal Daughter (2002), Diabolika II and Mean Cuisine (2003), Quibble Race (2004), I’m O.K. (2006). https://www.derekyu.com/games.html
Mossmouth, mossmouth.com (web, secondary; his company’s site): Mossmouth founded in 2009; its games. https://www.mossmouth.com/
Mossmouth, UFO 50 site and Steam page (web, secondary): the team, the premise, the 32-colour palette, release on 18 September 2024 (Steam) and 7 August 2025 (Switch). https://50games.fun/ and https://store.steampowered.com/app/1147860/UFO_50/
“Derek Yu” and “TIGSource”, Wikipedia (web, secondary): birth in Pasadena in 1982; TIGSource founded by Jordan Magnuson in 2005; I’m O.K. as a response to Jack Thompson; Diabolika (1999); Time Barons (2014); the idea for UFO 50 in 2016 and its remakes of Diabolika and Quibble Race. https://en.wikipedia.org/wiki/Derek_Yu