Who is the leader of the Horde during Battle for Azeroth?

The leader of the Horde during Battle for Azeroth was Sylvanas Windrunner, who held the title of Warchief. She became Warchief after Vol’jin, her predecessor, was mortally wounded during the Legion’s invasion of the Broken Isles.

Sylvanas had originally been a high elf ranger-general of Quel’thalas. The Scourge killed her during Arthas Menethil’s invasion, then raised her as a banshee. She eventually regained her free will, founded the Forsaken, and led them from the ruins of Lordaeron. Her people later joined the Horde under Thrall.

In Battle for Azeroth, Sylvanas attempted to strengthen the Horde’s control of Kalimdor and secure Azerite, a powerful resource released after Sargeras wounded Azeroth. Her campaign included the destruction of Teldrassil, the Night Elf World Tree, which triggered a wider war with the Alliance.

The main confusion is that Vol’jin, Garrosh Hellscream, and Thrall were also Horde Warchiefs, but at different points in the timeline. During Battle for Azeroth specifically, Sylvanas was the sitting Warchief until she abandoned the Horde after the confrontation at Orgrimmar.