Vengeance of Excalibur puts the player in control of a small team of Knights of the Round Table who will seek out in Spain for the stolen items of the treasure of Camelot (the series advances the timeline of Arthurian lore 500 years past period where it is usually established).

They then proceed to the treasure room of the castle and steal its contents, including Arthur's mythical sword Excalibur and the recently recovered Holy Grail.

Merlin is appointed acting regent of the realm while the Knights of the Round Table are dispatched in small groups to search the medieval western Europe and find a way to stop this mystic assault.

If they manage to negotiate these hazards, the forces of the Round Table must still find and defeat Sir Bruce and his ally, the Shadow Master.

The player is also presented with the chance to import four characters from Spirit of Excalibur, bringing the total number of knights that can be chosen up to sixteen.