Tessa Foxglove is a Therian Vix, a shapeshifter that can go back and forth from her red and blue foxlike form to her human form.

While she is in her Therian Vix form she is unable to be killed by anything other than the Spark of Finn.

She’s a master thief and a local creature of legend because she has never been caught. While in her human form she utilizes the vast amount of magical trinkets she’s collected to get herself in and out of trouble.

Hundreds of years ago her family was killed and since then she has been living with the purple glow-in-the-dark rabbits known as the Dalston Hares.