Astal (known as Kisuishou Densetsu Astal ((輝水晶伝説アスタル, "Shining Crystal Legend Astal") in Japan) is a platformer developed by Sega and published by Sega (in North America and Japan) and Brazilian company Tec Toy (in Brazil). A European released was planned, but got cancelled.

Somewhere in the universe, the Goddess Antowas created a world from a single jewel. To inhabit this world, she created two humans: from a green jewel, a girl, Leda, who has the power to make things live on Quartalia; and from a red Jewel, a boy, Astal, whose purpose was to protect Leda. Content with her creation, Antowas slept. During her sleep, the evil Jerado tried to take over Quartalia and created a warrior: Geist. Geist kidnapped Leda, and in an effort to get her back, Astal tore Quartalia apart, awakening Antowas. As punishment, Antowas banished Astal to Quartalia's moon. Leda took pity on Astal, and gave him her jewel. Once Astal and Jerado were dealt with, Antowas went back to sleep.

However, Geist was still free, and Quartalia was not restored from the changes Jerado wrought. From his prison on the moon, Astal witnessed Geist kidnap Leda again. Consumed with the need to protect her, he freed himself and returned to Quartalia. Now Astal journeys in search of Leda through a Quartalia transformed by Jerado's dark design.

Astal can jump perform various attacks. HE can grab an enemy and throw him, or he can punch while in the air. He can take a deep breath and blow out a firece gush of wind. The wind will destroy some enmies and disorient others. Astal can also punch on the ground to damage disoriented enemies. After the first stage, astal is accompanied by a bird. When Astal destory enemies surrounded by bright orbs, it will fill an enerby meter. If there is enough energy, Astal can make the bird perform several tasks, like fetching a health restoring fruit or attacking all enemies on screen. Fruit which restores energy can also be found in the levels.