Winds Gathers, Storm Rises

And the moment Valgrun heard about seven thousand horseman riding toward the Burka tribe, there was only one method that he could use to make sure that Burka tribe is not eradicated or destroyed.

Once Burka tribe is destroyed, then how could Haltur tribe who is relying on the three tribes around him to resist Chagai tribe.

if that happens the entire plan of Mayeux would crumble

Valgrun himself is a great strategist and he always have a way to break through certain problem.

The moment he heard that seven thousand horseman goes out, a plan come to his mind

Why is it that Khagai tribe who is small tribe in the west could survive for so long and for so many years manage to even compete with the other tribes around them?

Because most of them inherit the strategy of the ancient ancestors who once served in the Old Empires of the Steppe.