Mônica no Castelo do Dragão (Mônica in the Dragon's Castle) was the first game based on the popular Brazilian comic book series by Maurício de Souza to be released under the Tec Toy seal, for the Master System in Brazil. It is based off a rom hack from Wonder Boy in Monsterland, under the authorization of SEGA.
The story begins when Capitão Feio (Captain Ugly), one of the comic book series' only villains, plans to take over the world using an army of dirt. The game play was not changed from the original Wonder Boy game, and Mônica, the main character, can use all sorts of equipment, including her stuffed bunny, Sansão (Samson) as a weapon. Strangely enough, even though he is credited as the main villain of the game, Capitão Feio doesn't appear anywhere but the title screen.
One of the first big hits from Tec Toy, it was later introduced as a pack in with the Master System console as a programmed memory game, side by side with Sonic. Also, there was a special pink version of the Master System released with this game in order to attract the female public - albeit a very strange and chauvinist move by the company, it sold rather well and can still be bought in stores to this day, more than fifteen years after its original release.