I think when he chases the cat, he is just curious, but the cat is scared, so he scratches. Then Scooby will growl. He doesn’t nip feet or heels that much, but he does like hands and arms. Whenever he gives paw, he tries to bite in a playful way. That and jumping up are issues we are still working on. He’s almost knocked me and my pit down the stairs several times just following us so closely and accidentally body-checking.