Y'mhitra is a Miqo'te with white hair and fur, dressing in a cyan half-robe and black tights. Her weapon is a one-handed conjurer wand.
Having become proficient in arcanima, she takes the player to the Sagolii Desert where the essence of Ifrit can be summoned as an egi using the soul crystal. By defeating the entity in combat, Ifrit-Egi can be summoned into battle. Once Titan is defeated by the adventurer she will take him or her to Finder's Bluff in North Shroud where Titan-Egi is summoned and bent to the adventurer's will. A dark summoner accosts them, demanding they surrender the soul crystal, but they fend him off and escape.
She later learns it was a man named Tristan Nightflicker, and asks the adventurer to investigate his activities near Little Ala Mihgo. This leads to an attack by his associates that must be driven off. Once Garuda is slain at the Howling Eye she has Garuda-egi summoned atop the Floating City of Nym in Outer La Noscea.
Y'mithra also sends the adventurer to her colleagues at Saint Coinach's Find in Mor Dhona, who have unearthed garbs once worn by summoners of old. Eventually, Tristan is confronted in the Singing Shards, where it is discovered he was making deals with an Ascian to obtain power. In exchange for several crystals, the Ascian agrees to teach him how to summon the egi of an ancient primal, Belias. Y'mhitra and the player confront him and his new primal in a showdown.
When Alphinaud Leveilleur, Tataru Taru and the adventurer learn that Y'shtola's aetherial signature went to the Twelveswood, they seek out the help of the Elder Seedseer, Kan-E-Senna who informs them the process is not simple and mentions the possibility of a family member aiding it. Tataru exclaims that Y'shtola has a half-sister, Y'mhitra, who joined the Sons of Saint Coinach and is in Gridania. Y'mhitra tells the group that when she heard what happened to "Shtola" (her personal way of addressing her sister) she attempted to make contact with the missing Scion but to no avail. She reveals that though Y'shtola and herself are of different mothers, they share the same father. She agrees to help bring her back.
With Y'mhitra's presence, Kan-E-Senna, Raya-O-Senna and A-Ruhn-Senna locate Y'shtola in the Lifestream and retrieve her. Y'mhitra accompanies her unconscious sister while Kan-E-Senna advises the others to wait till she comes to.
Y'mhitra continues her role as an advisor to summoners. Rammbroes presents her with a tomestone containing information on more of Alagan summoning arts, and notes the Singing Shards might be suitable for drawing a lightning-aspected egi. However, they are unable to draw Ramuh-egi to the site to commit Austerities of Lightning.
There have been sightings a of a dark mage attacking travelers with Ifrit-egi in Thanalan. Working with Dancing Wolf of the Immortal Flames, they corner and defeat the mage in Northern Thanalan. Dancing Wolf explains it is the body of Tristan's brother, who was tempered by Ifrit. The Ascian of the Twelth Chalice appears, irritated at losing another pawn and reveals to be behind the incidents.
During her research on Summoner arts, Y'mhitra learned the reason they couldn't call forth Ramuh-egi was due to limited capacity of a summoner's lifeforce (having already harnessed three egis). She learns of another technique, called Trance, that can bypass these restrictions and allow the Summoner to harness the power of a primal directly. To combat the Ascian threat, she concludes the best option would be the Dreadwyrm Bahamut itself, whose fury was felt across the land in the Calamity. By sneaking into the Carteneau Flats, she has the adventurer meditate on Bahamut's influence. The Ascian of the Twelth Chalice attack with various egi, but once the Dreadwyrm Trance is mastered and his egi are destroyed, the Ascian flees.
Noting his sudden cowardice, Y'mhitra suspects lesser Ascians are unable to possess living hosts like the overlords (such as Lahabrea) in the event their old body is slain. Thinking they would need corpses to persist—and the restricted Carteneau Flats would not have any available—he wasn't going to risk dissipation at that point. She claims another technique is available, located in the Great Gubal Library. Outside the old facility the Ascian returns with three others to assist him. This was all part of Y'mhitra's plan: by tricking them into an ambush, and knowing the adventurer needed to be in the heat of battle to master the Dreadwyrm Trance (the library was a ruse), she lured them into the secluded Hinterlands where no readily available corpses would be nearby. The four Ascians are destroyed thanks to the adventurer's new mastery of Deathflare.
As a conjurer, Y'mhitra helps the adventurer to fight the egis in many of Summoner job quests, by providing healing support and guidance.
- Y'mhitra's location now is the same location as were Louisoix Leveilleur in the Sixth Astral Era and they both give quest related to a primal.
- One of Y'shtola's costumes in Dissidia Arcade resembles Y'mhitra, with a blue top that consists of grayish patterns, black trousers and white shoes.