Master Kohga is a character and a Boss from The Legend of Zelda: Breath of the Wild. He is the leader of the Yiga Clan during the events of Breath of the Wild, a group of Sheikah rebels devoted to Calamity Ganon. He is met in the Yiga Clan Hideout.
Kohga is informal, boisterous, and quick to lose his temper. He is very confident in his physical abilities, describing himself as "strong" and "burly." He seems to be a charismatic leader, as members of his clan will attempt to avenge him after his defeat.
As a Boss Master Kohga can be defeated by using the Stasis Rune and Magnesis Rune of the Sheikah Slate to stun him with his own boulders. Once stunned, most conventional weapons deal damage, but ranged ones will definitely be helpful as he often moves rapidly around the boss area. Eventually, he will unleash a massive boulder, large enough to obscure his view of Link, claiming it to be the ultimate technique of the Yiga Clan. However, the boulder ends up rolling towards him and falls down with him down the pit, with him declaring that the Yiga Clan will avenge him.
Defeating him allows Link to reclaim the stolen Thunder Helm for Gerudo Chief Makeela Riju. The Divine Beast Vah Naboris generates highly powerful lightning making it impossible to enter the dungeon, and the helm is required to protect Link and allow him to access and free the Divine Beast.