Throw It In: Web Comics
- Fluffmodeus in Something*Positive was introduced out of spite, but has actually been a well-received character.
- Maxim, the Bishōnen Jägermonster of Girl Genius, was originally created as a joke. But he was found so funny that he was added to the comic as-is.
- The same goes for the entire Jager race. In the first scene with Klaus, there was a big empty space next to him, so Phil drew a scruffy-looking soldier with sharp teeth.
- The Cyantian Chronicles: This page of the comic ''Akaelae'' The author posted this comment after speculation on who the involved characters were.
Actually, these two are the last two cameos. It was never mentioned that they were involved as characters... it was just too fitting to pass up with the dialogue that came to mind.
- Also, Cesilee's Diary was originally supposed to be only 6 strips long. It ended up far longer and was eventually combined with the former primary comic, Campus Safari.
- Vaarsuvius of The Order of the Stick was originally intended to have a definite gender. The fans did not immediately get this, and Rich Burlew decided to leave it ambiguous for laughs. Nowadays, V's Ambiguous Gender is both a Running Gag and in some places a dramatic plot point.
- A coloring error caused Precocious' Yvette to suddenly appear darker for a few days (compare her in this strip to her the next day). The author decided that she looked better this way and kept the new "dark Yvette"
- El Goonish Shive: According to the commentary in this strip the origin of the whole plot point of Nanase's rapid hair growth being magic related (and the storyline it inspired) stemmed from this strip in which Dan drew Nanase's hair too long too soon (given that it was only three weeks In-Universe since her last appearance when her hair was much shorter).
- A one-panel example in Concerned: author Chris Livingston was in the middle of making a strip when his wife made the off-the-cuff request that, at some point of the comic's run, protagonist Gordon Frohman use the expression, "Eep". Livingston promptly put the expression directly into the panel he was working on at that exact moment — thus having Gordon say "Eep" in response to getting blasted in the chest with a shotgun.
- Domain Tnemrot: The referee was never meant to be named and would just be a background character. Fans loved him, so he was given a bigger role.
- Many elements of Digger, including major characters and plot points, were invented on the spur of the moment.
- When the Commander and Jonesy went to the future in Manly Guys Doing Manly Things, the chaos left behind in the present was originally just going to be generic chaos, but then Twitch Plays Pokémon Red came out and Coelasquid was inspired to make a homage to it instead.
- Knights of Buena Vista does this In-Universe. Mary wants to give her Player Character policing skills, which is called "copper", but she wrote that for hair color, so others think this character is a Redheaded Hero. Mary shrugs and goes with it.