After obtaining aid from the lords of the realm in Ultima I, your character travels back in time, locates the mad wizard Mondain, slays him, and ends his reign of terror. In Ultima II: Revenge of the Enchantress, Mondain's protégé, Minax, who studied the mad wizard's teachings and writings, returns to wreak vengeance on the person who slew her teacher and lover -- you. And, instead of waiting for you to return to her native land of Sosaria, she wreaks havoc on your own Earth.
Throughout Ultima II: Revenge of the Enchantress, your quest is quite different in scope from its predecessor. Earth is turned into a half-modern, half-fantasy world by the forces of magic and, as a result, things are much stranger than one might expect. As explained in the introduction, your tasks in the game are to "Battle strange creatures across the face of the Earth, search for clues in careless words spoken at the local pub, traverse deep, dark, deadly dungeons and tall, terrifying towers...and conquer Time itself to battle Minax the Enchantress."
The game's graphics are CGA-compatible for the most part with the over world map, towns and castles utilizing a top-down perspective. Meanwhile, the dungeons, like those in Ultima I, are first-person monochrome wire frame constructions. PC speaker sound effects are used for certain aspects of the game.
The main quest in Ultima II: Revenge of the Enchantress is to find and defeat the evil Minax. While tracking down Mondain's avenger during your travels on Earth, a variety of weapons and armor are at your disposal, ranging from medieval blades to futuristic phasers -- all used to confront the myriad of fantasy monsters roaming your home planet.
Can you succeed once again in your quest to travel back in time and set things right? By slaying the Enchantress, you'll preserve order in your world and be rewarded by the knowledge of a job well done.