Of all the classic fantasy monsters out there, the mighty dragon is easily the most pervasive. What’s not to love about a good old giant reptile? Especially one that, among other common traits like flight and a penchant for great wisdom and magic, is capable of breathing fire? Not that all dragons have those qualities, mind you. But some kind of powerful elemental affinity does seem to be common.
But as we’ve already discussed, the “classic” dragon concept isn’t always the most naturalistic. In Europe, where the whole fire-breathing thing originated, dragons have taken all kinds of forms from snake-like and honestly not too far-fetched to ridiculous chimeric monstrosities. But these days, a form of four legs, two bat-like wings, and a more mammalian than reptilian gait seems to be the traditional image of the European dragon. Not to mention the whole “penchant for a wildly dangerous breath” bit.
Draconic biology
That being said, we’re far from the first ones to take a look at these beasties and ask, “What if we made them more believable?” Take the legs and wings as an example. Recently, the dragon’s improbable six-limbed body plan has frequently given way to a design inspired by pterosaurs like Quetzalcoatlus. These very real flying reptiles walked on all fours by using their mighty wings as forelegs when on the ground.
So, too, have authors and speculative biologists explored and explained the idea of breathing fire in a dozen different ways. E.E. Knight’s dragons eat oily meats and store the oils in a special gland for fuel. Anne McCaffrey’s consume rocks containing phosphine just before using it to fuel their fire. Flint-like structures for ignition have variously appeared in the teeth, specialized mouth organs, and even gizzards. And the dragons of the Skyrim video game forgo “breathing” fire altogether, instead speaking ancient words of power that magically generate not only flames but a dozen other devastating effects.
Controlling the burn
Ultimately, the main ingredients you need to start working with fire are oxygen, fuel, and something to ignite the fuel. Science journalist Bethany Brookshire has an excellent article on this topic as it relates to the dragon’s fire breath. In it, she explores a variety of readily flammable chemicals including iron sulfide gas and alcohols like ethanol and methanol. She suggests liquid fuels, possibly combined with gas in an aerosol spray, for better control of the fire’s movement and potentially easier storage in organs.
Of course, the best place to find unusual qualities for creatures is in animals that already have those qualities. While no known species can breathe fire, we do get something close with the bombardier beetle. Some species of this innocent-looking insect have a form of chemical deterrent that reaches scalding temperatures. They achieve this by storing two different liquids, hydrogen peroxide and hydroquinone, in small organs in the abdomen. When threatened, they mix the two chemicals in a specialized chamber and then immediately shoot the mixture at the threat. This mixture is highly exothermic, meaning the two chemicals react in a way that gives off a lot of heat. Meanwhile, the beetle ejects the reacting mixture quickly enough to keep from scalding itself in the process.
So, the solution here would be to store two different chemicals that, when mixed, cause an explosive or otherwise damaging chemical reaction. This is actually how fire works. It’s a chemical reaction between a combustible material and oxygen. Ignition is just what’s needed to get that reaction going. And for some materials, all the ignition “spark” needs is contact with the oxygen in the air.
Elemental weapons for everybody!
Of course, dragons don’t have to be the only ones using fire breath or other wild defenses to set off a memorable encounter. Heck, dragons don’t even have to be limited to breathing fire. As the bombardier beetle reminds us, the animal kingdom already has several examples of unusual and occasionally “elemental” forms of offense and defense.
As it turns out, a lot of offenses that show up in the form of projectiles are liquid in nature. While the bombardier beetle might be the most explosive, several insect species can spray acids and other irritating chemicals. And some snakes, known as “spitting” cobras, can shoot venom from specialized fangs. This venom might be less harmful on intact skin than it would be from a bite, but it can cause blindness if it gets into the eyes.
On the less caustic end, some animals can essentially shoot water or air. Archerfish can shoot small jets of water with impressive precision and force, at least for their small size. This force is enough to knock the insects they eat from perches above the water. Meanwhile, the claw snaps of pistol shrimp and punches of some mantis shrimp are so quick and forceful that they make cavitation bubbles. These vapor-filled cavities in the water create shockwaves strong enough to stun or even kill small fish.
Perhaps the most famous “unusual” attack that doesn’t come from venom is found in electric eels. These famous fish can deliver powerful electric shocks to stun both predators and prey. And while electric eels and the handful of other electrifying fish can’t quite shoot lighting, at least some of them can leap from the water to deliver their shocks to threats that are only partially submerged.
Natural weapons for unnatural animals
So in addition to superheated liquids, we have real life examples of acid, toxin, water jet, shockwave, and electric attacks. These are some hefty attributes for fantastical beasts! How exactly their “powers” are used would depend, naturally, on what the species expects to face and whether it’s food, a threat, or both. Going back to our example of dragons, maybe yours spits a boiling or burning chemical as a defense against even larger predators rather than literally breathing fire. Or, maybe it can ignite said chemical with a mechanism in the mouth, and uses fire to flush out and later cook the dragon’s prey. Maybe it can do both!
Or maybe we’re instead looking at a sea monster with an upscaled version of the archerfish’s water jet. Imagine one of those things aiming powerful sprays of seawater at sailors who lean a little too far over the railing.
Incidentally, I think I just found a terrifying new encounter for a sailing-related ttrpg campaign.
Sources: Bethany Brookshire’s article, Bombardier beetles in the Natural History Museum, Electric eels in the National Library of Medicine