The Zhentarim are a vast organization of criminals who use flying snakes as messengers. The waffle crew was attacked by Zhentarim assassins in Port Nyanzaru. They were trying to snatch the ring of winter.  When the heroes returned to Port Nyanzaru, the Zhentarim unsuccessfully attempted to poison their food.  While sailing to Waterdeep, the group spotted and engaged with members of the Zhentarim who were also sailing to Waterdeep.  Once they arrived at the city, the group saw that Wandala was allied with them. Together, they fought off an attack by agents of the Xanathar.  Naska, a dwarven member of the Zhentarim, asked the heroes to help him kill a mind flayer ally of the Xanathar.