Crystalis takes place 100 years after the world was saved by humans building a tower in the sky to watch over the globe and combat "evil". The mysterious hero from the cryogenic chamber must uncover the mystery of the tower. Along his journey, he will meet four wise people who will teach him magic, aid him on his quest.
The gameplay involves exploring dungeons and fighting monsters to gain experience points and gold. The hero can equip weapons, armor, shields, and magical items, as well as use elemental swords for powerful ranged attacks. As the hero levels up, he gains access to new areas and battles against tougher enemies.