To make it clear, I consider parts of D&D hit points a metacurrancy just baked in and rolled together with actual injury recording in a confusing way. It also includes some defensive skill done in a backwards way, but that's sort of the issue; its almost impossible to pluck out durability, avoidance and luck because its piled up in one spot, and sometimes that's a problem.
With all due respect, that's not how Metacurrencies work. They're a resource that's spent to "help the character".
Metacurrency is a type of player resource that is spent and exchanged at the player level without any kind of resource exchange manifesting in the game world. It is distinct both from in-game resources (such as ammunition or gold coins) and from mechanical abstractions of fictional events (such...
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According to Gary & Tim (Kask), Hit Points are an abstract that emulates (like you pointed out) durability, avoidance and luck.
It's all perspective, though. McClane vs. a hand-picked team of well-armed terrorists. He shoots (okay, he shoots four or five times) , he kills a terrorist. Terrorist unloads a full clip, McClane is "missed". Is he a super-monk/Rogue (unarmored AC, high DEX, evasion against "full Auto" AoE attack)? Or is he "hit" dozens of times, consuming "luck/divinefavor/stamina" in the form of hit points? Maybe a Hero Bennie to negate a critical hit or three?
(Of course, as you say, it could simply be McClane is just simply high level against a bunch of mooks. He attacks 3 times for 20 damage and kills the 15hp mook; they attack one time each, hit sometimes and miss sometimes, and his 135 hp just don't care; after a Short Rest, he just spends some HD, and is back at it in the next scene...)
Legolas is... a DMNPC. ;-P Plus, he clearly nat1's getting on the horse in the second movie, spends an Inspiration/HeroPoint to reroll, and gets a nat20 and tries to make it look like he didn't totally fail in the first place!
Well yeah, it is all perspective. I'm not quoting from a Science Journal or the Bible. This is all just my opinion and I could be wrong as a broken clock:
Just so we're on the same page, McClane (in Die Hard) was battling
thieves, not terrorists

So - D&D-wise (because some people seem to only understand ttrpgs through the blurred lens of that one rpg) - the Fighter takes on a gang of bandits. And wins because he's smart and tough and a little lucky. But that's reflected in dice rolls: sometimes you get those high rolls that make all the difference. He didn't get a Short Rest because he was constantly on the move trying to stay a step ahead of Hans (again, smart). He had plenty of HP & a high CON (Fighter stuff) but most importantly, he avoided combat as much as possible, picking his spots and staying mobile.
SMART - unlike many players who rarely use any kind of tactics then blame the TPK on the GM
On "Die Hard" as D&D scenario:
John McClane is above gritty tier and in the low end action movie hero tier. He's about 6th level character, probably Fighter/Rogue with 18 DEX (or you could stat him up in D20 Modern) and pretty decent CON (16?) and all-around good attributes.
No way an 18 DEX - that's peak human, equivalent to an Olympic-level gymnast. 18 CON? Definitely. He had to be ridiculously tough to endure that beating. Of course, low CHA which reflects in how he drives everyone crazy including his estranged wife
He has a few destiny points/inspiration to reroll saving throws or negate critical hits, and enough hit points that the first few attempts to shoot him even if they hit would only cause superficial flesh wounds.
I don't see the need for Metacurrency - McClane is just a tough SOB. He doesn't get nailed by the bad guys because they're thieves not operators, so they don't shoot well. Not as well as McClane, an experienced NYC police detective.
He's up against a group of 3rd level NPC bad guys with a mixture of classes (some fighters, some rogues, some experts) who seem to be mostly gritty tier characters with believable abilities if outsized personalities. The BBEG Hans Gruber is a 3rd level rogue with 18 INT and high CHR. He's meant to be a mastermind, not a tough opponent on his own and he's built around skills.
Hans is (if we're using D&D) high INT/WIS/CHA and a higher level than McClane. Definitely a Rogue (Mastermind?) who pieced together a master plan that only fails because McClane was accidentally invited to the party.
The dragon Karl Vreski is a 3rd fighter with 18 STR and CON, as well as feats that make him a very difficult melee opponent.
McClane is against 11 3rd level characters, but notably circumstances mean that a) they can't concentrate on him with all their forces at once and b) he initially has surprise. As long as he doesn't have to deal with more than 2 bad guys at once, he has the advantage. Four or more is potentially deadly, and eight would be suicide.
Honestly, the whole "no shoes" thing just rigs the scenario to make it artificially difficult.
I agree with all this. McClane takes advantage of the building's size and once he gets the detonators, it throws off Gruber's plan, which further helps McClane. The "no shoes" is classic drama (Hans knows John has no shoes so he tells Karl to shoot the glass, hoping to trap McClane - but John shocks Hans & himself by deciding to run across the broken glass anyway). If GMs can create similar scenes, they're very memorable (or at least frustrating) for the players
The problem is, these two characters are not similar.
McCain is, indeed capable, but he's also capable of missing, doesn't show his tactical acumen is so good that he's incapable of taking a bullet somewhere.
Right: McClane is a great cop, but he's also human and totally out of his element. As a marksman, John is levels above the average cop
Across the course of the movie an awful lot of them fly his way. Even accounting for how bad shots are when under pressure, he'd be unlikely to completely avoid them (or as reliably put them into others) even as good as he is.
Karl shoots him, but McClane's outstanding attributes are his toughness and his wit. He doesn't beat Karl due to luck - he's just the better man
He's also extremely lucky. And that luck is not something you can reliably expect in a game barring an additional mechanism.
Players have that same luck. I've put players in the worst possible positions so many times thinking the TPK was coming and the dice saved them over and over and over again. No Metacurrency needed. It's the beauty of rolling dice in ttrpgs: the randomness is dramatic - and the players love it when their PCs escape certain death
Legolas, is, on the other hand, an exceptional individual among a species that is already superhuman and shows it. He does things no other character in the movie/book seems likely capable of, and if there is one, its likely another elf. He still most likely could be hit, but the number of incoming attacks you'd need before it would be particularly likely is most likely larger than the number you see aimed in his direction, and that's not accounting for the fact his superhuman mobility (and it is superhuman; the books spell out that the footing of elves is better than any human, orc or dwarf can have) usually keeps him out of range of some attacks.
Yeah. He's an Elf and I'm pretty sure he's the reason Elves were so OP in early D&D. If I never see another Elven Fighter/Magic-User/Thief again
The two characters are really doing an apples and oranges comparison.
My point was both characters were very capable and clearly outclassed their opponents, even when impaired by complications (injury, bad positioning, running out of ammo). Many of us played old D&D editions without Metacurrencies for decades and our PCs did fine - usually. Sometimes. Metacurrencies take the randomness out of gameplay by negating bad dice rolls and those rolls - combined with ability/skill bonuses - are meant to emulate fictional heroes. I mean, if the PCs just winwinwin all the time in every situation, I wouldn't call that playing a game and that definitely doesn't fit the fiction that inspired the games in the first place.
You want "realism"? Learn to embrace the occasional failure.