In my universe I have small dragons that are capable of bringing down much larger prey with highly acidic venom that can be sprayed over distance as a thick jet or a fine mist. Ideally I’d like this “breath” attack to be as devastating as possible, even to large animals, and be able to bring down prey very quickly. Now the obvious answer to this would be hydrochloric acid, or less obvious sulfuric acid. However, I was thinking something a little more spectacular. Enter fluoroantimonic acid, the much bigger and badder brother of all the other acids we have made. This stuff makes the Xenomorph blood in Alien look like tap water. It eats through most materials, usually explodes or bursts into flame on contact with other materials, and leaves behind a highly toxic cloud. Very heavy metal.

But I have a problem, or a couple related problems to be more exact. How can this dragon make this stuff, and how can it store it without killing itself? If this is pretty much impossible on principle alone, then what other acid could it use that would still have a very showy and fantastic result?

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    $\begingroup$ "Superacids are acids with an acidity greater than that of 100% pure sulfuric acid." (Wikipedia) In particular, fluoroantimonic acid is stored in PTFE containers. $\endgroup$
    – AlexP
    Commented Apr 11, 2018 at 15:43
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    $\begingroup$ Never got formic acid on your skin? It's called formic because it is naturally made by fire ants $\endgroup$
    – L.Dutch
    Commented Apr 11, 2018 at 15:48
  • $\begingroup$ How small are these small dragons? $\endgroup$
    – RonJohn
    Commented Apr 11, 2018 at 15:57
  • $\begingroup$ @RonJohn Let’s say 1 or 2 feet long. $\endgroup$
    – Nick
    Commented Apr 11, 2018 at 16:02
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    $\begingroup$ Here's a closely related question that I asked some time back. Your question might be considered an outright duplicate of mine; I essentially asked for the nastiest acid a creature could use (most likely as a spray) without killing itself in the process, and how said creature would store and utilize that acid. At the least, it might give you some useful pointers. $\endgroup$
    – Palarran
    Commented Apr 11, 2018 at 17:27

1 Answer 1


Acids with exotic components are difficult to store in biological systems and difficult to synthesize - where is an animal going to find fluorine and antimony?

But worse: a cloud of flame or of acid does not have much knockdown power. People who are doused in gasoline can go running off and jump in a pool. Later on it is very bad for them and they will likely die of their burns but acutely it is not a good way to make something stop moving so it can be eaten. Even if the flame / acid blinds the animal it will still go running off and will fight you if it feels you.

Snakes do it up as regards knockdown power. A dragon could be a snake. A flying snake with a venom breath weapon would be formidable. Spitting snakes are exactly this except not flying.

Your dragon sprays a mist of venom which combines tissue destructive enzymes and anticoagulants. The showy and fantastic result: after breathing this venom, two or three coughs later the target animal explosively exsanguinates from massive pulmonary hemorrhage.

You do not need to invent much to come up with a venom that could do this. Info on snake venom pasted below with more at source.

Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise

Often, extensive local tissue damage develops (Fig 2), characterised by necrosis of the affected limb and requiring surgical debridement or amputation if left untreated. Hydrolytic enzymes, such as snake venom metalloproteinases (SVMPs) and PLA2s, and non‐enzymatic cytotoxic 3FTXs have been implicated as the causative agents found in different snake venoms (Escalante et al, 2009; Rivel et al, 2016). Recently it was shown that the destruction of local tissue may also be promoted by snake venom inducing the formation of neutrophil extracellular traps (NETs), which in turn block blood vessels and contain the venom toxins to bite site, thereby promoting cytotoxic pathology (Katkar et al, 2016)... Haemorrhage caused by snake venom is often complicated and exacerbated by patients presenting with blood clotting disturbances as the result of venom‐induced consumption coagulopathy (VICC). VICC, a disseminated intravascular coagulation (DIC)‐like syndrome, is characterised by low or undetectable levels of fibrinogen, resulting in incoagulable blood (Fig 2) (Isbister, 2010; Maduwage & Isbister, 2014).

  • $\begingroup$ Definitely showy and fantastic! I also like the fact that this venom could be easily used as a chemical weapon in war, clouds of instant death gas rendering entire areas completely off limits. $\endgroup$
    – Nick
    Commented Apr 11, 2018 at 16:07
  • $\begingroup$ A Chrysopelea snake can glide which could help make this snake more dragonlike $\endgroup$
    – Amoeba
    Commented Apr 11, 2018 at 20:00
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    $\begingroup$ Something to note: not all creatures need "knockdown power". Consider humans: before we started up with agriculture and technology and so on, ancient humans utilized endurance hunting, which basically entailed wounding prey and then running it to exhaustion. Under those circumstances, even a slower-acting acid could be deadly; hydrofluoric acid, for instance, takes a few hours (depending on concentration) but can lead to nasty burns and severe shock or cardiac arrest, and doubles as a contact poison. $\endgroup$
    – Palarran
    Commented Apr 12, 2018 at 3:37

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