The Gypsy is the person that sends the Stranger on the journey to become the Avatar, and thus an immensely important figure in Ultima lore.
Using the eight Cards of Virtue to pose a series of seven moral dilemmas, she uses the Stranger's answers to determine which virtue is favored the most at the beginning of the Quest of the Avatar in the Character Creation, as well as starting abilities.
The Avatar remembered her in Ultima V and Ultima VI, although there is some disparity in the memory of her. The Avatar met her again in Ultima IX.
In Ultima IV, the answers determine the starting stats, magic abilities, place and equipment... as well as which companion cannot join the party.
In Ultima V and VI, the answers determine the starting stats.
In Ultima IX, the answers determine stating stats, mana storage and equipment.
The Gypsy's appearance at the beginning of Ultima IX is identical to that of Morganna of Minoc.
The MMORPG World of Warcraft pays homage to the Ultima series by including a fortune teller, Sayge at the Darkmoon Faire, who poses similar moral dilemmas. The answers to his questions determine which stats will receive a temporary "buff."
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