He has been writing serious fics since at least 2006. In the Telltale Fanfic Theater 3000 MST of Sue Mary stories, he tells that his favorite genre is humor, and his previous attempts at drama didn't work out as well.
According to the MarrissaTheWriter Complete Anthology, Doombly first encountered trollfics through a World of Warcraft machinima video based on Peter Chimaera's epic Castlevania: Wisps of Dracula. He thus wrote a parody of trollfics and Mary Sues, who he named Sue Mary, into his Danny Phantom fanfic Oh Gosh No! Not Another Oh Gosh No! Story!. Later, he began writing fanfics exclusively as Sue, beginning with another Danny Phantom story, SamB ecomes a Halfa1111. The idea of Sue largely draws inspiration from an infamous Harry Potter fanfic My Immortal and its main character Ebony Dark'ness Dementia Raven Way, albeit with influences from other trollfic writers.
MarissaTheWriter came to him in a separate idea, which he describes as "My Immortal written in the style of Dark Yagami" and later "what if I wrote a story that was terrible, but also able to appear genuine". While Sue Mary's stories were mostly short stories based on whatever movie she happened to see at cinema last, MarissaTheWriter writes longer stories for fandoms such as Portal, which, as Doombly noted, "needed its own My Immortal".
Around the same time as ITS MY LIFE! and TEEN FORTRESS 2, Doombly also wrote stories for Portal 2 seriously. One such story, Bring Your Daughter to Work Day, features a cameo of Marrissa Roberts. Others include Being Human, a human!Wheatley story that has its own TV Tropes page, and Portal Cubed, an attempt at continuing the story of Portal 2. Eventually, though, he moved away from fanfics in general, as THE MARRISSA GAMES and Real Beauty were updated only sparingly.
In 2014, he returned to writing both serious fics and Sue Mary trollfics. This time, he became inspired by BioShock Infinite, as his first serious story after the hiatus, Robert & Rosalind are Dead, continues the story of the Infinite DLC Burial at Sea, and his first Sue Mary story after Real Beauty, THE STRAIN COMES TO SESAME STREET, features, among other characters, the Lutece "twins" themselves. So far, unlike his Marrissa and Sue Mary stories, they were only MSTed once, by Tumblr user transcontinentalempire.
Main article: MarissaTheWriter
Typically, it is presumed that MarissaTheWriter and Marrissa Roberts are Doombly's self-inserts. However, this does not stop him from appearing in Meanie Pixies' Hour of Fame, as an incarnation of Marrissa Roberts after a disagreement between her and Principal Business Lady, as well as the coming of Pokémon Go. There, he has also become a cult leader for a group worshiping the "Lettuce" twins, known as the "Lettucest fandom". Later, he and a resurrected Business Lady are announced as the co-mayors of "the new city of Portal High School", a city founded in the Fourth Creation by himself, Wheatly NEO and Chell Joy Roberts.
While Doombly doesn't appear in any other MarissaTheWriter stories, and the authorial role is taken by Marissa herself, he does appear in five ASBusinessMagnet stories unrelated to Marrissa. In the first one, Official Fanfiction University: Portal: The 4th Millennium Edition, he, as the author of TEEN FORTRESS 2, was sent to the Warweary Serket's school. The Warweary, later on, threatens him due to turning Business Man into a falmer troll in Invader Zim: Born Again Christian.
In the second story, Violet and the Horrible Fanfic Writer, he is mentioned as having trouble writing Real Beauty when he suddenly gets the news that ASBusinessMagnet is now in the body of Violet Beauregarde. He then proceeds to go back to the time of Charlie and the Chocolate Factory and insists on calling Violet "Business Man", but she is unmoved and proceeds to enter the factory, along with the other four kids, without giving much thought on Doombly's thoughts. He still continues his plans of rescue, but they eventually trap him in Wonka's factory, which he escapes only years later in the sequel, Violet and the Partner in Crime to Literature. In this sequel, he also gets to visit both ASBusinessMagnet in Violet's body in Paris and Wonka's factory, where he witnesses the reversal of the body swap. This is later explored in another story, Mike Teavee, Mystery Hunter, as he and Mike Teavee enter a dialogue.
In the fifth story, Just Before the Anthology, he is a more major character. He starts off similarly to Violet and the Horrible Fanfic Writer, having trouble writing Real Beauty, but seeing as this time the story is completely different, he learns that ASBusinessMagnet is dying. He thus heads to Lithuania, where he meets Skepkitty. Together, they head into "the dream world" to try and find "Business Man" there, and in the process make a complete mockery of the Charlie and the Chocolate Factory universe.
In addition, he was once referenced by MarissaTheWriter in Chapter 3 of Real Beauty. Marissa comments that she had forgotten the password to her own Tumblr due to the falmer trollz, and as such contacted Doombly to instead post the chapter on his blog.
For a listing of his Sue Mary fanfics and his own MSTs of them, see Sue Mary#Bibliography.
- ITS MY LIFE!
- TEEN FORTRESS 2
- Invader Zim: Born Again Christian
- THE MARRISSA GAMES
- Real Beauty
- MarrissaTheWriter Complete Anthology (credited as contributor, interviewed)
- HARRY POTTER AN THE KILL OF SNAPE
- ITS MY LIFE!: THE FLAMES AWAKENS
- Various other stories:
- Halflife: Fulllife Consequences: Binds of Freedome
- BioShock Infinite: Full Lutece Consequences
- Post-SCrash Session (Author's notes only)
- Post-SCrash Session 3: Spectators of the Host (Author's notes only)
- Violet and the Horrible Fanfic Writer (First appearance)
- Real Beauty (Author's notes only)
- Meanie Pixies' Hour of Fame
- ↑ " At 12:00 AM EST I will be 22!" - Doombly, September 27, 2015 - URL: http://doombly.tumblr.com/post/130037819814/at-1200-am-est-i-will-be-22