[header] How to stop a cat from biting or scratching during play [title] Recognize play aggression. [step] If your cat's ears flatten, its tail flickers and it stares at you, it may be exhibiting play aggression. However, it shouldn't look like your cat is in pain. 
There shouldn't be any growling or hissing sounds, which could indicate more serious forms of aggression due to physical pain or injury. [substeps] If your cat is exhibiting aggression and you don't know if it is play aggression or aggression due to a serious illness, you should get it checked out by a veterinarian.