Zhako

"The four khals commanded almost 80,000 horsemen between them."

- Jorah Mormont

Khal Zhako is an unseen character in Game of Thrones. He is not expected to appear in the series, being long dead when it begins.

History
Khal Zhako was one of four khals who fought in what later became known as the Field of Crows.

In the books
In the A Song of Ice and Fire novels, Khal Zhako was one of four khals who fought in the Field of Crows, with the others being Haro, Qano, and Loso. His khalasar attacked from the south when the Dothraki surrounded the Sarnori.