Katia reaches 98% on a gnoll and the system calls her one — a near-miss that terrifies Carl more than a success would.
The doppelganger skill that once managed a 65% likeness of Hekla has become something else. Trying to spare Growler Gary his deaths, Katia Grim works and works at a gnoll shape to fool the magical key on the Interdiction Rapid-Response Railway Repair Cart, and gets it to 98% accuracy; on her last attempt the system itself designates her a gnoll. It still does not work — the cart's hand consoles want a gnoll's actual left hand, not a gnoll's nameplate — but the attempt is the closest anyone has come to talking the dungeon out of a blood price.
What it does to Carl is quieter. Watching her emerge as a flawless hyena-faced gnoll, he finds the skill, used this way, genuinely terrifying, and it changes his mind about her build: the charisma points he had privately thought wasted now look like the beginning of the perfect spy, if her self-confidence keeps improving. Her newest points have gone into constitution instead, and the disguise that nearly saved Gary's life sits unused while Mongo does the work.
Katia's own frame reshaped into a flawless hyena-faced gnoll, indistinguishable enough that the system files her as one.
The near-solution to the cart problem, and the proof that Katia's disguises have outgrown mere resemblance.