Blackclaw is your typical stray-in-training. Both his parents are henchcats, though he doesn't see them often (they aren't the most caring cats in the world). Like most strays, his coloring is black, though his tail is striped with a golden-yellow, as is a stripe across his chest. He gets his name from his solitary black claw on his right front paw.

Blackclaw is one of the more prominent strays-in-training. He shows tremendous promise and potential, and Macavity has started grooming him to be the next leader of his criminal organization. He is a member of the elite master pouncers, and one of the first cats Nefret meets when she is brought to Macavity's lair. The two hit it off, but trouble soon ensues in the form of a Jellicle 'rescue'. The Jellicles were fought off, but they got close enough to see Macavity, Solitaire, and Blackclaw defending Nefret. He feels an odd attraction to the stubborn kitten (she's a lot like her dad and Munkustrap combined - eek!), but has an inner feeling that nothing will ever come of it. But in spite of this feeling, he confronts her on the eve of another rescue attempt...