Animal transformation with fleshcrafting magic, but it happens gradually. The victim getting their skin changed slowly, hands and feet slowly turning into hooves, fingers and toes fusing with time, spine curving to become more suited for quadrupedal locomotion, face elongating to more and more resemble the animal, each day another pain as their bones and organs are rearranged/transformed slowly. At some point, talking will become impossible, and even instincts and preferences start to change that of the animal, but the memories of the human that used to be remain which only torments the victim more.
The close ones of the victim helplessly watch them turn day by day in agonizing fashion. And when it's over, when the transformation is done, they are left with the situation of having to look after the now animal victim for life, like a twisted pet, hoping against hope that there would be another mage whose expertise in fleshcraft can turn the victim back to human. Yet no matter what the mage does they can never fully bring back what once was, there is no magic or curse to undo you see, the best they can do is to fleshcraft the victim into the approximation of the blurry memories others have of them. Hope will keep them going for some time, prolonging their suffering. And if the hope eventually fails, they will have to face the reality that it just might be better to put the victim down, that is if the victim doesn't just run away and throw themselves off a cliff first.
