Scientific achievement
Somewhere in what is now the Posuidete Archipelago; when the region consisted of significantly larger islands, in a Sarrukh city the first yuan-ti was created after an experimentation amalgamating human and reptilians together. These first generations of yuan-ti were used as a slave race by the Sarrukh. In the years after this, the Sarrukh of the region would also create the first lizardfolk, in addition to numerous other reptilian humanoids.