Fireboy and Watergirl

Fireboy and Watergirl (stylized as Fireboy & Watergirl) is a puzzle-platform video game series created by indie game developer Oslo Albet in 2009. The first five games in the series were released on the now defunct software platform Adobe Flash but can still be played on the online web portal Cool Math Games as they were converted to HTML5.

Gameplay
Fireboy and Watergirl is a cooperative puzzle-platform game. Fireboy can be moved by using the arrow keys and Watergirl can be moved using the WAD keys. Fireboy can only go through fire whereas Watergirl can only go through water.

Development
Oslo Albet said that he developed Fireboy and Watergirl because he had "always found puzzle games to be fascinating". He finalized the game mechanics before creating the characters as he was more interested in the game play. Albet said it was "pretty obvious" that he required two characters with opposing elements for the game to feel natural to players and designed Fireboy first before spending "quite a bit of time" finding the right design for Watergirl. After several changes, he designed Watergirl's "waterfall" ponytail to counter Fireboy's fiery hair. He added that when developing the story and characters he knew that they had to appeal to "boys, girls and families as a whole".

Release
The first game in the series, Fireboy and Watergirl in the Forest Temple, was released in 2009 on the software platform Adobe Flash and hosted on the online web portal Cool Math Games as the games' target demographic is 10 to 15 year olds. In June 2019, it was rumoured that Cool Math Games would be shutting down as Adobe Flash was set to be discontinued in 2020 but the company confirmed that they would continue to operate and Flash games such as Fireboy and Watergirl were later converted into HTML5. The sixth game in the series, Fireboy and Watergirl: Fairy Tales, was released on Steam on November 1, 2021.

Reception
GamerBolt praised the pacing of the game by stating that the "too-easy" introductory levels did not take too long to complete before the game became more challenging. They stated that the game was "extremely well-executed" and there was a "decent number of levels" which meant the game potentially had several hours of gameplay. However, they stated that it did not necessarily have the complexity or the longevity to compete with other 2D platforming games such as Spelunky or Super Meat Boy.

Daria Paterek of Impact cited Fireboy and Watergirl as a game that made her "fall in love with gaming" and praised the games' replay value as each new instalment has levels of varying difficulty and takes place in a distinct setting such as a forest, a desert and during winter. Nicole Clark of Polygon described the game as a "classic" and said that playing it "feels like traveling back in time". Clark stated that fans of Fireboy and Watergirl had found characters in Pixar's Elemental to be similar in design, though she said that elemental characters were not a novel idea citing Avatar: The Last Airbender and The Adventures of Sharkboy and Lavagirl as examples.