He has every reason to fear the Wookie.
She would be a good full back for the Washington Redskins.
The teeth on that monster would make a Pit Bull frightened.
Chewbacca: Aaaaaaaaaaaaaaaarrrgh!
C-3PO: He made a fair move. Screaming about it can’t help you.
Han Solo: Let him have it. It’s not wise to upset a Wookiee.
C-3PO: But sir, nobody worries about upsetting a droid.
Han Solo: That’s ‘cause droids don’t pull people’s arms out of their sockets when they lose. Wookiees are known to do that.
Chewbacca: Grrf.
C-3PO: I see your point, sir. I suggest a new strategy, R2: let the Wookiee win.