Gathwen is a Bosmer who comes running for help near the Temple of the Mourning Springs. She and her master, Rurelion, were shipwrecked,[source?] so they came to the temple when they heard that the water never ran dry—referring to the Mourning Stone.
Gathwen, Rurelion, and Ealcil went on an expedition into the Temple of the Mourning springs prior to "Tears of the Two Moons." They found the Mourning Stone, which, to them, was something of great use; however, upon grabbing it, undead legions attacked the party, causing Rurelion to be trapped inside the temple. Although Ealcil returned to Eagle's Strand, Gathwen remained, looking for someone to help get her master to safety.
Gathwen is devoted to her master; she refuses to abandon him in the temple—unlike Ealcil. Upon learning that Uldor has control over Rurelion, she fears for him, and urges caution. She is also be modest, for when Rurelion suggests that he be sealed away with Uldor, and that Gathwen will be more powerful than him one day, she states that she is nothing compared to him, and that she can be lost without consequence.
Upon reaching the Temple of the Mourning Springs, she asks the Vestige for help in saving her master, Rurelion, who has been unable to escape the temple. After accepting, the pair is warned by a skeleton, who tells that Rurelion is under his control, right before two wards are cast on the entrance to the catacombs. Gathwen tells how they must be dispelled before they can enter, which she volunteers to do. As the Vestige distracts the undead around both the scorpion and spider sigils, Gathwen takes them down, allowing for access into the catacombs.
Inside, Gathwen hints that the puzzle that would deactivate the barrier to the next room relates to the cycle of the two moons—Secunda and Masser. After the code is solved, she will advise caution before entering the next room.
Rurelion can be found inside the ritual room, but Gathwen will appear distressed; this is because he has been possessed by Uldor, an undead Maormer wizard, who explains his plan to take over Eagle's Strand by summoning more skeletons. As the Vestige kills his minions, she applies magic to the bone piles, making Uldor unable to use them anymore. After Rurelion fights for his body, Gathwen will instruct the Vestige to follow him alone as she takes a minute to rest.
After deactivating the traps, Rurelion will suggest that he tells Uldor to take over his body while the Vestige places the Tears of the Two Moons on pedestals in the tomb, while Gathwen fetch the Mourning Stone to close off the area, forever. Upon entering the Great Hall, she will come in and disagree with the plan, instead volunteering to sacrifice herself instead. The Vestige has to choose whether to seal Rurelion or Gathwen inside the tomb.
If Rurelion is chosen, then she will get the Mourning Stone from Eagle's Strand. After the Vestige emerges alone, she will swear that she will free Rurelion from Uldor eventually, rewarding him or her with the Mourning Bow.
If Gathwen is chosen, then she will instruct Uldor to take her over; once the four stones are placed, she will give a final farewell.
If Gathwen is chosen to live, then she will offer to help the Vestige battle the Sea Vipers.
In combat, Gathwen serves as more of an auxiliary combatant, rarely engaging the enemy directly, but assisting the Vestige from behind.
Gathwen can heal both herself and the Vestige during battle. Her spells can prove to be a useful assist in a battle against numerous enemies.
Gathwen can dispel and derune numerous wards and rituals by Uldor. Although she does not use this ability directly in combat, her ability helps progress through the quest, and, therefore, fight less enemies overall.
- If the Vestige wanders away from the temple, she will remark that he or she is going in the wrong direction. Despite this, she will still follow him or her.