Yisht

Yisht is a warrior from the Ice Tribes of great renown. Her patron is the emperor’s sister Sherzal. She act as mentor to her ward Zole and her bodyguard at Sweet Mercy. However, Yisht has a mysterious mission of her own, to steal the convent's Shipheart. When she succeeds, she becomes possessed by a host of Demons.

Appearance
Yisht is a fairly short woman, with dark hair usually drawn back behind her head in a severe bun. She has the features common to the Ice Tribes, skin with a reddish hint and prominent cheekbones. Her eyes are flat and dead like a shark. Yisht has strong Marjal traits, which give her the magical ability to predict her opponent’s actions in a fight. It is also revealed that she has a rare talent for Rock-Work, able to manipulate and transform stone.

After being infected with Demons from holding the Sweet Mercy Shipheart, she is described as having multiple inflamed colours of red and purple moving across her body. Her eyes also change from cold to becoming truly angry.

Personality
Yisht is shown to be cold, calculating, and utterly merciless, threatening to kill Nona Grey's friend Hessa if she interferes with her protégé. She is also very taciturn and rarely speaks. Common to most of the Ice Tribes she's very tough, ruthless, cold and merciless. She believes friends are a weakness and that emotions hinder a fighter. She stops short of true cruelty, at least in her own mind. She kills the crippled Hessa for the temerity of manipulating her with Threads. After becoming possess with Demons from contact with the Shipheart, she even admits to having become truly cruel, exemplified in their fight in Sherzal's palace hallway.

Abilities
Yisht is a very powerful Marjal, likely a full-blood. Her specific talent is Rock-Working, which she used to steal Sweet Mercy's Shipheart. While fighting it is said by the novices that she can see a few seconds in the future, beating even the fastest Hunskas. However Keot claims that's not the case, that instead Nona's moves are simply too predictable.

History
Yisht’s past is unclear, but she has a great reputation for her skills as a warrior. Sherzal first employs Yisht as mentor and teacher for her ward Zole, along with Safira and a Noi-Guin. Zole is a Four-Blood, possessing the traits of all of the original tribes of men, something virtually unheard of in history.

Red Sister
Some two years after Nona joins Sweet Mercy, Sherzal pays a visit to the convent, wanting Zole to join as a novice. While Abbess Glass tries to refuse, High Priest Nevis insists, and she’s eventually enrolled in Grey Class. Yisht is allowed to stay in the convent guest quarters to act as Zole’s bodyguard. Yisht takes an immediate dislike to Nona, threatening her friend Hessa if Nona goes anywhere near Zole.

Prior to the Caltess Forging, Sister Tallow hones the skills of Blade Class by having them spar with Yisht, all twelve novices at once. Yisht proves a wonder, able to foresee whatever the attackers will do next, and defeating them all down, except for Zole.

Meanwhile, all the novices notice Yisht’s strange behaviour around the convent, who seems to be searching for something. However, the Abbess seems remarkably tolerant of her, fearing that Sherzal will take back the precious Zole from the Ancestor Church. When Nona becomes sick after the Caltess Forging, she fears she’s been poisoned by Raymel Tacsis. While searching the caves beneath the convent for the ingredients for a cure, Nona comes across Yisht secretly tunnelling for something with her Marjal Rock-Working skills.

Nona eventually realises that Yisht is trying to steal the Shipheart. Clera, Ara, and the other novices agree to help deal with her, since the Abbess probably won't. Together they steal the ingredients for Boneless, and Nona tries to poison Yisht by surprise. Yet even in the dark, Yisht predicts her actions, but still gets some of the Boneless on herself, and Nona eventually manages to subdue the deadly ice-triber. The other novices then drag Yisht out of the caverns, stuff her in a wine-barrel, and ship her to Durn.

However, somehow Yisht manages to return to Sweet Mercy while most of the novices are away on the Ranging. Hessa senses her return and make her laborious way through the caves to the Shipheart cavern. Yisht has made extraordinary progress, with her Rock-Worker ability enhanced by proximity to the Shipheart. As Yisht breaks through to the Shipheart, and begins tunnelling away, Hessa pulls on all Yisht’s Threads hurling her back. However, Hessa doesn’t have the ruthlessness to actually kill Yisht, giving her a chance to collapse the cave over Hessa. Despite Nona sending her Shadow through her Thread-Bond to help her friend, Yisht kills Hessa, and makes her escape.

Grey Sister
Yisht still works for Sherzal, but has changed. Her prolonged contact with the Sweet Mercy Shipheart has left her possessed by countless Demons, that can be glimpsed writhing on her skin. She was always cold and ruthless, but now can be truly cruel. Sherzal's guards are frightened of her, and Clera terrified, avoiding her at all cost.

Nona, Clera and Sister Kettle encounter Yisht when they sneak into Sherzal's palace to try and steal back the Church's only Shipheart. A fight ensues with Nona using all she’s learned in sword-fighting and Kettle unleashing her Rending-Shadows, but Yisht's skills prove too great, able to predict her enemy's every move. Yisht tries to force Nona to flee by threatening the injured Kettle, first cutting her throat and then holding Grey Mustard poison over the prone nun. But Nona refuses to leave her friend. This act of compassion forces Keot, the Demon inside Nona, to leap from her into Yisht. The introduction of yet another Demon inside Yisht, causes her to stagger away writhing, and allow Nona and Kettle to escape.