Silly Question: How do you get your Sim to transform into a werewolf?

"Kerrigan;c-18131358" wrote:
The Transformation Mastery trait appears if your Werewolf becomes Furious and goes on a Rampage but you don't scare any sims. You can kind of cheat and just lock the door to the room the Werewolf is in. I got it by accident when my Sims was rampaging while everyone else was asleep. Since no one woke up and got scared she got Mastery. Fury still builds and you'll have unintentional changes but you can transform on purpose with the power.