Repond

The enchantment Repond is both useful and unpredictable. Made specifically to counter the rampaging hoards of orcs, goblins, and trolls that infested the lands of Sosaria during the third Age of Darkness, it was available to all practitioners of arcane magic at the time. When used against an aggressive party of such humanoids, it had a 50% chance of destroying a random portion of the opposing force (from one to 8 attackers). Its fallacy was that it could only be attempted once in any given combat, whether the creatures were successfully destroyed or not, and regardless of which spellcaster attempted it.

Though Repond proved ineffective after the fall of Exodus, its effects were recalled and referenced as late as Ultima Underworld.

Trivia

 * Due to Ultima III's random method of choosing which opposing creatures are destroyed, Repond can occasionally be cast successfully, but not affect any targets.