In fact, the Groke does little more than stare from the shadows but everyone fears her. Ace!
What I really love about the Groke, however, is the fact that she may be misunderstood. In Moominland Midwinter, she is drawn by the midwinter bonfire and sits on it in an attempt to get warm. Everyone flees from her in terror. She is lonely, cold and isolated. In the end Moomintroll feels sorry for her.
A truly three dimensional villian...in fact, maybe not a villain at all!