Isaac Kuo diaspora
@Michael Moceri Yeah, it's just so different. I mean, obviously we have a cultural mythology of St George and the dragon, where he defeats the dragon with a spear. But I find that imagery a bit ... odd ... I mean, the dragon is tiny! It's always depicted as smaller than St George's horse, and sometimes much smaller even than St George himself.

At some point, we've gotten a more modern image of the dragon as being a huge creature - but still the idea of a medieval looking knight fighting it. That at least looks more impressive and heroic.

But if we actually did some serious world building, the requirements and challenges are just so different from historical military needs ... it deserves a rethink.
In the RPG the black eye a dragonslayer is a huge pike for two dwarves. But I always doubted its use against a huge dragon.
@Rasmus Fuhse Well, obviously they can make their dragons "weak" enough to be vulnerable to a huge pike. The challenges and practicality of wielding a huge pike with two humanoids is an interesting thing to ponder, though.
Two things about Saint George's dragon to remember:
  • The danger it posed was because it was a venomous monster. More or less a cockatrice. I think in some versions it breathed toxic clouds. So its danger wasn't really intended to be physical strength. It poisoned the lands and the waters.
  • Saint George won by the grace of God more than by strength of arms. As much as anything else, the story was highly political. It was about taking up arms to become a vessel for God's might against toxic heathen beliefs. It seems obvious, for instance, that toxic breath is a great stand in for the words spoken by non-Christian religions.
Making the dragon small and easy for a holy person to dispatch, then, is kind of the point. "Look," the story says. "Marching down into the Holy Land is an easy victory for those who go with the grace of God!"

Is that useful for this conversation? Maybe? Are we positing a world where people can use that sort of magic?
I took a few minutes to really really think about this. I guess, Michael Moceri is pretty close with the net thrower. Gladiators had some nets they threw at ferocious beasts in the colosseum. If you could craft a net that is light in weight (maybe in some elvish cord) with some weights at the outside of the net. If you rotate the net, it will automatically become a frisbee. So the aim is to throw the net in a slightly rotating state at the dragon. If the net is light enough it can be larger in its diameter. Maybe we need to build a throwing machine that looks like a balista.

Alright, sounds like a plan. Now where is this dragon we're talking about?
A net is cool looking in a gladiatorial arena, but it has VERY short range. This is, of course, a good safety feature for the audience.

In real world hunting, hunters would use bolas instead. Same basic idea, but much better range. Not good for a gladiator fight because it could result in frequent audience injuries and/or death. But great for hunting.

So, you have two or three weights on the ends of long chains. This might be launched like a hammer throw, or launched from the tip of a pole. You plant the pole into the ground and then wrench it into a circular motion - basically throwing your weight around like a hammer throw but you remain facing forward toward the target.

I think wrenching around a pole would be superior to spinning yourself around in a hammer throw, but it does involve carrying this 8' long pole around with you. (Technically a spear, but the conical point is only really good at poking into the ground.)
Okay I've thought more about the pole launch system ... I like it.

The pole looks a bit like a long sword. The tip is a somewhat blunt conical point. The shaft is a hollow pole. There is a large "cross guard" which you hole with your hands. And the other end is a corkscrew shape.

Why a corkscrew? That way, the projectile gets released after a set number of turns, aligned in the correct direction. This makes the weapon a lot easier to aim, and also a LOT safer for everyone else on the range.
... OTOH, studying hammer throw movement, there's no way the pole launch system is going to match that sort of power. The thing is, a hammer thrower does this thing similar to ice skaters where they pull in their whole body to a nearly vertical line. This insanely amps up the rotation. If you throw your weight around, you're just never going to be able to achieve that effect.
Okay, to get some idea of how powerful an Olympic hammer throw is, consider that the projectile has the same mass and range as a Chinese Crouching tiger trebuchet (7.25kg, 78m range).

However, that trebuchet had a crew of 70. A hammer throw is accomplished by just one person.

Some further thoughts ...

I just realized that there was a historical target similar in size and toughness to a giant dragon - a sailing ship. If the ancient Greeks or Romans could have figured out a weapon to kill a ship, they certainly would have used it! But they didn't. Furthermore, historical weapons were evidently not very effective at taking out sails, so it's plausibly not feasible to seriously damage a dragon's wings.

So basically, it seems hopeless for any sort of man portable ballista to do the job. If they could, then Romans would have figured out to line the deck of a warship with them and take out enemy ships with them. But nope ... the only really effective weapon to directly take out a ship was the ram.

So, I return to the hammer throw. I don't think the chackram idea will really work out ... historically, chainshot wasn't really all that effective at taking out sails, and that was with crazy powerful cannon balls propelled by gunpowder. But the big dart might work to punch through a dragon's hide.

I started with the idea of a giant plumbata, but a long steel pole with a sharp point could penetrate better. So, it's a big dart, with the rope attached near the tip and the tail. You launch using a two handed technique, releasing the tip just barely before the tail to neutralize its rotation.

This two handed technique also allows the dart to be used as a melee weapon ... possibly to execute a coup de grace.
I still think that your step one is some sort of lure, unless it's plausible and a good idea to get them in their lairs. Trying to take something out on the wing in this context, with these sorts of weapons, is going to be essentially impossible.

So what are you using as a lure, and how can you use that to your advantage? Poison? A big fucking fish hook?

Which also makes me wonder how smart these things are. Could you stake out a goat with a big metal fish hook tied to it and count on the dragon to swallow the thing more or less whole, getting the hook caught in its throat? That'd be awesome, both for immobilizing the thing to hit it with weapons, and to keep it from flaming you immediately.
If you can trick it to take poison, then that could be a great way to circumvent the size and power disadvantage. But my experience with trying to give pets medicine ... sigh ... if only it were that easy.

A fishing hook is interesting out-of-the-box thinking. But why is that? Obviously, fishing hooks work well with fish, and also some squid I think. But I don't think they've been used for any sort of land or flying animals?

Obviously it's not a given that a dragon would eat its prey whole. If you look at eagles or big cats, they'll something first and then gnaw/pick at it. But many fish eating creatures eat their prey whole simply because fish are slippery things. Swallowing a fish whole is the most efficient way to dispatch the prey and also ensure it doesn't literally slip away. I would guess that fishing hooks could theoretically be used to go after some some fish eating birds like herons or pelicans.

But I'm guessing that it's not going to work on a dragon that likes to eat goats.

Hmm ... okay, thinking about it ... the basic problem is the ground. If you're a big cat and you wanted to just take a prey whole like a big fish slurping up a little fish ... you'd get your chin jammed into the dirt. It just doesn't really work. Underwater, it's a whole different story.

So a dragon isn't going to be going around swallowing goats whole simply because the ground kind of gets in the way of that lifestyle.
I agree. I chose an image for that which is purposefully silly to act as a bit of a starting point.

Because I'm thoroughly convinced that you're not going to be able to hunt a dragon on the wing with muscle powered weapons. The idea is preposterous. They'd likely soar quite high and move very quickly, because their hunting range would need to be huge.

You need something that'll get them to land. That's the only way you'll be able to aim enough power at them to cause real damage.

The idea of a hook isn't like when you're catching a fish. With a fish, you're relying on the hook to bear the weight of the whole animal for long enough to get it into the boat or a net. That's not reasonable with something like a dragon, because it's just too big.

Instead, it's to immobilize it for a moment and distract it with pain. If you're lucky, it gets hooked facing away from you so it can't flame you until it rips the hook out. Which all basically goes to say that it's to buy you a second during which you can initiate your actual attack.

Does it have to be a hook? Nope. The only thing you absolutely need is for it to land. A hook or a barbed spear through the wing flaps would be better than nothing, but that stuff is just to give you a moment of advantage. Which would be great if you're dealing with a flying murder machine. But perhaps not strictly necessary.

I suspect that a dragon would hunt one of two ways.

The first is a flyby with fire. It takes one pass to loose Hell. Then it either lands and eats, or it snatches and carries.

The second way is just to swoop quickly and grab with its claws and fly off. Particularly squirmy prey animals are likely to be dropped from height to finish them off, the picked up again. Otherwise killing them is whenever it's convenient.

So how are you figuring the things hunt? Does swooping of breathing fire happen first? Do they eat on the spot or tend toward carry out? If either is an option, does the behavior vary in a predictable way, such as by prey animal?
I am imagining the second way, swooping in like an eagle and just carrying the prey off. Squirming is not really a problem because those talons are just crazy big and sharp, and there's like 8 of them piercing deep in the victim's body.

Alternatively though:

As for fire breathing ... well, to be honest I think we need to reject fire breathing as too unrealistic or there's really nothing puny non-magical humans can do other than hide and hope for the best. Either that or it's a relatively weak sort of flame and not like a Churchill Crocodile flame thrower.

What use is a weak flame? Well, it could be similar to how some whales use bubbles to corral a school of fish and then they just swallow whole gobs of them. Setting a circular fire around a herd of beasts could trap them and allow a dragon to just slay a bunch en masse rather than expend a lot of energy simply chasing them down.

This would be a good match for a long neck. A gigantic heron-like dragon is not going to be a stealth hunter, but it could efficiently just walk among this fire panicked herd and strike victim after victim. In contrast, the way an eagle does this sort of hopping talon kicks is ... clumsy and inelegant. The lighting thrust of a heron bill is more like it.

So what does this mean for dragon hunters?

1) With the eagle paradigm ... good luck! This eagle-like dragon could just strike anywhere and there's not an obvious way to bait it.

2) With the herd slayer paradigm ... ah, now we're cooking. There's only going to be so many big herds around, and only some will be located in conditions suitable for fire corralling. This gives dragon hunters places to stake out and maybe even lure in the dragon with a bait herd somehow. Furthermore, the chaos of the herd slaughter gives dragon hunters the chance to slip in close enough to attack. If it's too risky to brave the fire, it's also possible to try and take on the dragon after the slaughter, during the dragon's eating phase.

Note the during the eating phase, there will probably be a lot of scavengers annoying the dragon. So, there will still be a significant amount of motion and distractions to allow the hunters to try and sneak in close.

As for various tricks to try and get a momentary advantage over the dragon? I'm skeptical. You've still got to somehow back it up with an effective attack. First figure out basically how that attack works, then see if some sort of momentary distraction is worth the bother.

The attack I'm suggesting is maybe a team of six hunters attacking from 20-50m with hammer throw darts. The throw itself takes maybe 7 seconds, so hopefully not enough time for the dragon realize what's going on, lift off, and get climb out of range.
Okay - a completely different approach ... DART RIDING. So, let's posit that we can bait the dragon to some place below a tall mountain, or we have hot air balloon technology. The dragon hunters are equipped with parachutes, and they ride gigantic darts.

Unlike normal darts, which only have fletchings at the rear, these gigantic darts have cruciform wings at both the front and rear (like a Sidewinder missile). The pilot rides this dart as it plummets toward the dragon, and then (maybe) deploys the parachute at the last second.

Note that it's possible to steer via weight shifting, but more control authority is possible with missile-like control surfaces.

The big advantage of manned darts is that they can be very powerful.

The disadvantages? I hope several would be self evident ...