Blacktooth was a male ferret in the Thousand Eye Army. Along with Splitnose, he was in charge of a patrol that raided Ben Stickle's home and took their last five loaves of bread. When he was attacked and beaten up by Martin the Warrior, though he was injured in the process, he did take Martin to Kotir. After being sent after Martin the Warrior, Gonff, and Young Dinny with Splitnose and Scratch, he was killed by Splitnose during an argument.
Blacktooth had a love for food, such as grilled baby trout with butter. Once, at one of Verdauga Greeneyes' plunder feasts, he had a bowl of cold Strawberry Cordial with two mint leaves up his ears, much to Scratch's disgust. While tracking Martin, Gonff, and Young Dinny, he and Splitnose played a game where they called out their favorite foods, much to the chagrin of Scratch.
While Martin and his friends were sleeping, Blacktooth and Splitnose sneaked up on them and threatened to kill Young Dinny. They tied the trio up and began eating food from their sack of provisions. The two started arguing and fought; and Splitnose killed Blacktooth. Splitnose regretted killing his friend, however he fell into a sinkhole shortly thereafter.