Alex Kidd in Miracle World for the Master System was the first game in Sega's Alex Kidd series. Before Sonic, Alex Kidd was created as Sega's mascot in response to the popularity of Super Mario. The game was designed by Kotaro Hayashida (aka Ossale Kohta), with art by Rieko Kodama, and music composed by Tokuhiko Uwabo.
Alex Kidd in Miracle World also became a pack-in game from 1990 onwards; it was included in the system BIOS for Master System II consoles. The built in version contained a graphical change where Alex was shown eating a hamburger on the map, and the jump/punch controls were swapped.
The game takes place on the planet Aries (aka Miracle World), where Alex Kidd discovers he is the lost son of the kingdom of Radaxian, which has recently been conquered by Janken the Great. Janken has kidnapped Alex's brother, Prince Egle, and his fiancée, Lora. Alex, who had spent several years training in the shellcore fighting technique in isolation, returns to save the kingdom.
The game is primarily a platformer like Super Mario, but features some light RPG elements. Alex can use his punch to attack enemies or break rocks. Certain rocks contain an evil spirit that will try to kill Alex when released; others can contain a jump power-up. Alex can only take one hit before losing a life.
Money collected throughout the game can be used to purchase vehicles to help him through the stages. Vehicles for purchase include motorbikes and "peticopters" (small pedal-powered helicopters).
The game features 17 stages; each ends when Alex collects a piece of food at the end of the stage. It also features 4 bosses, including Janken and his 3 henchmen. To defeat the bosses ,Alex must best them in a game of jan-ken-pon (rock, paper, scissors).
Alex Kidd in Miracle World is available on Wii Virtual Console and PSN, and was also included in the Xbox Live Sega Vintage Collection Alex Kidd & Co, which includes Super Hang-On and The Revenge of Shinobi.