Black Bokoblin serve as the Level 3 Bokoblin type in Breath of the Wild, being stronger than the Red Bokoblin and the Blue Bokoblin. They have significantly more health and wield much stronger weapons.
Black Bokoblin are not very common at all in the early portions of the game, and instead, are found on the outskirts of the map. They are commonly found within the Gerudo Desert of the Wasteland, Gerudo Highlands, Tabantha, Hebra, and Akkala regions. Black Bokoblins wield much stronger varieties of Boko weaponry, including Spiked Boko Club and Dragonbone Boko Club, as well as several non-Boko weapons, such as the Dragonbone Moblin Spear, Enhanced Lizal Spear, Dragonbone Moblin Club, and the Spiked Boko Bat. These enemies also appear on Horseback, most commonly in the Hebra region, where they usually wield Dragon Bone Boko Bows,
Hyrule Compendium entry of the Black Bokoblin.