Mystell

Mystell is a resident of Killorn Keep, responsible for the inner security.

When she met the Avatar for the first time in Ultima Underworld II, she tested the hero on knowledge and loyalty to the Guardian. Not knowing the Avatar's identity, Mystell revealed that she was the ears and eyes of the Guardian in the keep, trying to root out any traitors, voicing her suspicion about Altara.

The Avatar warned Altara, and protected her from Mystell, who in turn scolded the Avatar for killing Relk, who had uncovered the identity of the Avatar, but had no opportunity to warn Mystell. Later, she was found in the yellow zone of the Ethereal Void, dreaming of hoping to please the Guardian who sent her to this place every night to find the Shrine of Spirituality.

When the Avatar later returned to Killorn Keep, it turned out that Mors Gotha had practically relieved her of her post, making her doubt if she had been loyal enough to the Guardian.

Trivia

 * The Avatar can tell her that his/her name is Abraham Lincoln.
 * Also, if the Avatar mentions being an opponent of the Guardian, Mystell merely thinks it's a joke.