Gotham.
Before entering Gotham, Yun Hexian had cautiously asked Pang Xin to scout how many registered bat-cubs currently belonged to Batman's family. Fortunately, neither too many nor too few—there were five in total.
Dick Grayson (police officer AKA Nightwing), Jason Todd (Red Hood AKA socially deceased), Tim Drake (student and dual CEO of Drake and Wayne Enterprises AKA Red Robin), Damian Wayne (student AKA Robin and part-time heir to the Assassin Alliance), and Cassandra Cain (Black Bat), who was far away in Hong Kong.
Chapter 386