Of the three, the most human-looking of the Yuan-ti are the Purebloods. The transformed beings fall into three main categories: abominations, malisons, and Purebloods. These evil deeds allowed them to become snakelike hybrids and stripped them completely of all emotion. In order to take their intellectual pursuits to new heights, they vowed to separate themselves from emotion by pledging themselves to the serpent gods, and in doing so performed terrible acts of human sacrifice and cannibalism.
Their ancient civilization worshipped snakes, as snakes embodied all of the qualities they wished to model themselves after. To read more about this, visit our D&D Race Guide. Tasha's Cauldron of Everything has added the 'Customizing Your Origin' option that may affect the ability score increases, languages, and proficiencies in this guide.