Greg has two faces...sleepy man and "What you talking 'bout Willis" man. The latter of the two is marked by big eyes, an open mouth, and arched eyebrows. He really isn't mad, but if you didn't know him then you would think he is out to kill you. Below is an archetypical example of his "Willis" pose. Enjoy!
Amber thought that in order to junxtapose Greg's face with happiness I should include a nice Idahoan sunset.