Spellbreaker is an interactive fiction computer game written by Dave Lebling and released by Infocom in 1985, the third and final game in the "Enchanter Trilogy". Like most of Infocom's games, it was released for many of the time's popular computer platforms, such as the Commodore 64, Atari ST and Apple II. It is Infocom's eighteenth game.

Over the course of events in the trilogy's earlier games from 956 to 957 GUE (Enchanter and Sorcerer), the player's character has progressed from a novice wizard possessing a few weak spells to the leader of the Circle of Enchanters. Now, in 966 GUE (ten years after the events of Enchanter), the very foundations of Magic itself seem to be failing, and the leaders of all the Guilds in the land have gathered to demand answers. In the midst of this impassioned meeting, the crowd is suddenly transformed into a group of toads and newts. Everyone present is affected except for the player and a shadowy figure who flees the hall.

You distinguished yourself among the young Enchanters by defeating the evil warlock Krill, whose attempt to subjugate the land was thwarted by your cleverness, as your inexperience allowed you to succeed where others might have failed. This earned you a place on the Circle of Enchanters, second only to the great Belboz the Necromancer. Then Belboz himself was nearly destroyed, and your rescue of him from the evil demon Jeearr earned you the ultimate honor given a mage, the leadership of the Circle of Enchanters.

Now, a crisis has befallen the kingdom. Magic itself seems to be failing. Spells fail to work or go strangely awry, the populace is confused and restive, and even the Enchanters Guild is baffled. A great conclave of the Guildmasters is ordained, and it is at this conclave that the final conflict between good and evil begins to unfold.