We all know the scene: It starts when a character in a fantasy story swears an oath. An oath... in blood. He dramatically unsheathes a knife, places it across his palm, and makes a fist before running the blade through his hand.
If you're anything like me, that's probably your first thought every time a character executes a Dramatic Palm-Slice. Yowch.
Your second thought is probably, "Why the palm?"
I mean, seriously, why? I know it's cool-looking in the moment, but have you ever had a deep cut on your palm? It sucks. It's possibly the worst place on your entire body to sustain a deep cut. (Okay, second-worst.)
Furthermore it's just impractical. If you need to draw blood for an arcane ritual, or demonstrate to your new liege-lord that you're serious about supporting him, must you also take one of your hands out of commission for the next week or two? Not only are you running the risk of infection, you're crippling yourself at a time where it's likely super-important that you're operating at full capacity. You did just make a blood-oath, after all.
I've been re-watching Season 2 of Game of Thrones, and an early episode has got a doozy of a Dramatic Palm-Slice. The charismatic Xaro Xhoan Daxos calls out some sort of loophole to get Daenerys into Qarth, and in doing so, he cuts the shit out of his palm and shows it to the rest of The Thirteen.
I'm sure you guys in Qarth have everything you need to take care of that cut—this is the greatest city that ever was or will be, after all. All the same, aren't you in the least bit worried about infection? Don't you need that hand? It looks so painful. Couldn't you have demonstrated your support for the Mother of Dragons in a way that was a bit less crippling?
It so happened that I saw another Dramatic Palm-Slice this weekend while replaying the middle chapter of The Witcher 2. While passing through the dwarven town of Vergen, Geralt the Witcher heads across a valley filled with a cursed fog to visit with Henselt, King of Kaedwen and leader of the opposing army. Geralt needs to get a bit of Henselt's blood to help lift the curse. (It's a bit more complicated than that, but that's the gist.)
Henselt is preparing to lead his men into battle, and is happy that the curse will be lifted, as he's itching for a fight. He agrees to give Geralt some blood. So what does he do? He slices the bejesus out of his hand in order to give Geralt the blood he needs. His right hand, too! Maybe he's a southpaw? But even then.
Dude, Geralt only said he needed some blood! He didn't say from where! You could've like, lightly cut the outside of your arm, or nicked your shoulder or something. You didn't have to take one of your entire hands out of commission the night before a huge battle. Some people don't think ahead at all.
This scene from The Lord of the Rings: The Two Towers always stuck with me, too. The camera really lingers on the leader of the Dunlendings as he painfully swears fealty to Saruman. Blood everywhere, immediately.
I'm sure that this is part of your hill-folk tradition and everything, but dude, you're the leader of your people, you might need that hand in the weeks to come. Plus, it looks like you haven't taken a shower in a year or something. You know that sucker is gonna get infected. Maybe there's a reason the people of Rohan were able to drive your people into the mountains? You sure don't seem to care much about hygiene.
This last example, from Robin Hood: Prince of Thieves, is one of the first times I ever saw someone perform a Dramatic Palm-Slice.
Robin swears to avenge his father's death by killing Hans Gruber, a dastardly man who is also Sheriff of Nottingham. And just so you know he's serious, he swears it by lacerating his hand. Even as a kid, when I saw this part, I remember thinking, "What the hell are you doing, Robin? It's not exactly going to be an easy fight! Maybe you could just swear it really hard, and then save your hand and have a better chance of survival? Just a thought."
I doubt the Dramatic Palm-Slice trope is going anywhere. As long as fantasy dudes and dudettes need to show their friends that they're really super serious about something, they'll probably still do so by cutting the shit out of their hands.
All the same; kings, queens, heroes and villains of the world, I beseech you: At least consider using some disinfectant on that mess. Otherwise it's gonna itch.