Hey Guys! This is my take on what was going on during 4x13 in Klaus and Caroline's minds. Italics is their thoughts, or, what they wish they could have / should have said. Enjoy!
Ever since the doppleganger, the witch, and the hunter had disappeared, Klaus had just stood there, staring at his brother's body. He felt no hunger. He felt no rage. He felt no sadness. He felt... nothing. A younger vampire would have foolishly claimed that his emotions were turned off, but he was old enough to know better. No, Klaus was still in shock. His baby brother was dead. What more was there to say?
He could hear someone approaching the house, and his original senses knew it was his first hybrid. He had nothing to say to the boy, and simply continued to stare at Kol. He kept thinking that any moment now, his brother would jump up, claim it was a joke, then laugh and say something crass. But no matter how long he waited, Kol did not move.
"Morning, Sunshine. You look pathetic."
Klaus stayed there, not moving. The boy wasn't even worth his time. He knew that the idiot wouldn't be stupid enough to enter the living room, and that proved all that Klaus needed that the boy was still scared of him. How stupid was he? Klaus would get out of here eventually, and when he did, Tyler already had a place on the list of those that needed to die in this town.
"Only until Bonnie's spell locking me in here wears off. Then I'll look different." You are lucky I am still in here. I only look pathetic because the rage I that is building up is not pouring out of me. I only look pathetic because you are hiding from me. You only say that because you know that I am still the Original Hybrid, and you are still weak and powerless against me.
Klaus turned around to face Tyler, and let his confidence ooze out of his look. "Angrier, perhaps. Or I won't look like anything cause I'll have gouged your eyeballs from their sockets." That's right, boy. I'm going to rip out your eyeballs first, then rip out your tongue, and tear you apart, slowly, until you beg for me to be done with you. You and the rest of this town will burn around me.
Tyler didn't move into the room, but he showed no fear in his position. "My friends will be back with the cure by then, so I can shove it down your throat and make you mortal."
It was almost hilarious, how Tyler seemed to think that he would ever be stronger than Klaus. He was a thousand years older and stronger. At no point would he have a chance to do anything to Klaus, let alone force feed him some cure. "I'm an Original. What makes you think my entire Vampire bloodline won't be cured along with me? I.E., you." Even if you do get that chance, I will still be the Original, and a Werewolf at that. I will still rip you limb from limb before you can even touch me.
"You know what I think?" Tyler pushed himself off of the wall he was leaning against, and Klaus could feel himself waiting, prepared, for Tyler to step through the barrier. If he was stupid enough to come through, Klaus would go ahead and destroy him now. He had a few days before the barrier came down, and that was plenty of time to torture and kill him. "I think that's impossible. I think the moment you stop being a Vampire, our whole blood connection to you is broken, and your sire line ceases to exist. So whatever happens to you?, happens ONLY to YOU. Which means I can kill your ass and no one else has to die. Although, I am still debating just how to do it."
Oh, this was too easy. Absolutely too bloody easy. There was no way he could resist this moment. Tyler looked like a boy trying to stand against his father, and Klaus was having none of his bullshit. Oh no, this boy was about to be put in his place, regardless of the fact he was stuck behind this barrier. He pushed forward at Vamp Speed immediately and spoke.
"I recommend drowning. There's nothing quite like the feeling of someone fighting for something as basic as human breath, and let me tell you, your mother was a fighter." I should have tortured her first, in front of you. I should have made you face the consequences of your actions. You will see, one day, the consequences played out before you. In the meantime, remember, I took away the thing most precious to you.
He couldn't help the smile that hid in his lips, and Tyler no longer looked so strong. Klaus knew he had struck deep with his words. Oh yes, he was going to torture this boy well, starting with drowning. Oh, it wouldn't kill him, but for someone still so used to breathing, it would be a wonderful way to start.