Po Bidau Gustang

Po Biduh Gustang is the head of the Biduh Family, and is one of the 10 Great Warriors. He was the first living being to systematically record Shinsoo. This hints that he may have been a Wave Controller.

Powers and Abilities
Being one of the 10 Great Warriors, he is incredibly powerful. Since he is the first living being to systematically record Shinsoo, he must have immense control over Shinsoo.