I got the idea from ~ShadowyNight
who made a face expression sheet for his character. (@Raph: I am too lazy to do ALL the "normal" expressions you did, so I just made up several retarded ones and placed them on one paper haha)
Also, I feel like hands can be very important in understanding the expressions completely.
-------1. PLEADING FOR HIS LIFE.
He is actually really good at this. And that's saying something about his life.
->He is resourceful and has a silver tongue, but- to be honest... If Kaz were ever to be captured, there is a great danger he would betray EVERYONE. He would give all the information to the enemy and endanger everyone should his acting fail him.2. BEING A SMUG JERK
He feels so safe looking down from the rooftops.
"I stole your precious... whatever this ugly thing is. You'll have to catch me if you want it back..."3. LOST IN THOUGHTS
It's actually not easy for me to make a character look "through" you, instead "at you". I practiced drawing this expression solely to see if I can make him look as if he's so deep in thought that he isn't actually looking at anything. I dunno if I succeeded.4. BEING THREATENED
Usually Kaz would piss his pants if he found himself with a blade under his chin- not make such an angry face.
If he looks like this when threatened- he probably secretly has a situation under control.5. SUSPICIOUS
To Kaz, everything is suspicious. People are suspicious. Animals are acting suspicious. The price of the bread that morning is suspicious.
He is a character who trusts no one and, to his ears, every word someone utters is a lie until proven otherwise.