What does it mean when your furbys eyes turn black?

When a Furby's eyes turn black, it typically indicates that the toy is entering a "sleep" or low-power mode. This can happen when the Furby has not been interacted with for a while, or its batteries are running low. In some cases, it may also signify that the Furby is experiencing a malfunction. To reactivate it, try playing with it or replacing its batteries.