Thanks to Swiftnissity for sending us the following.
At the end of teen wolfs season 3 final, Kate Argent (played by Jill Wagner) appeared as an unknown supernatural creature. It appears she's leaked what that creature is on twitter (a Were Jaguar). They are also known in Mexican folklore as 'Balam'.
Enter the were jaguar@MTVteenwolf— Jill Wagner (@JillWagner) March 25, 2014