Guide - Skyhaven Dragons

Origins
Dragons were around long before written records came into existence.  There are innumerable species, subspecies, and races of dragons, many of which interbreed (making classification a nightmare for mythozoologists), but the variety discussed here is the relatively common Skyhaven dragon.  Adults of this species can measure over a hundred feet long at maturity.

Habitat
Skyhaven dragons, and indeed most dragons of the "Western" variety, will live pretty much everywhere, but they need plenty of room to roam and a place to store their hoard.  A cave or abandoned castle will serve nicely, though some dragons are more creative; one eccentric dragon stole a wagon, carrying his hoard around in it as he wandered Tirialle.

Feeding
Dragons are carnivorous, and splendid hunters of all size game, though naturally they prefer larger animals such as elk, cattle, bison, buffalo, equines, or even (where available) elephants.  Being reptiles, they don't require as much food as a mammal their size would, but they still need plenty of hunting space.  They also obtain a fair amount of life-sustaining energy from their hoards (see Culture, below), lessening their drain on the land even further.  A dragon who overhunts is usually one with an unhealthily small hoard, though some overhunters are simply gluttonous.
Contrary to slanderous legends, most dragons can't stand the taste of human flesh, though they are not above biting in self defense.   The flame-scorched armor, human bones, and skulls so often depicted around dragon lairs are usually the results of trade, either with other beings who find the taste more agreeable or with humans themselves.  The grisly artefacts act as an effective deterrent to thieves, and some dragons find the relics aesthetically pleasing, not unlike lawn ornaments.

Life Cycle
Most dragons lay distinctive eggs; Skyhaven dragon eggs are smooth-shelled and oval, one to two feet long, with a speckled, even glittery color.  They are laid in clutches of three to seven in stony nests, often near volcanic vents or other sources of great heat.  If none is available, the mother dragon keeps the eggs warm by digging a rock hollow and heating the stones red- to white-hot with her flames.  It takes upwards of ten years for a Skyhaven dragon egg to hatch, during which time it is cared for lovingly by the mother dragon and, usually, the father.  After hatching, the young grow quickly, but are not ready to leave home until they are roughly 30 to 50 years old.  They sometimes return after that, but by their first century dragons are usually independent beings.
Immature young adult dragons often wander, seeking adventure and excitement.  They may study magic or other arts during this time, or they may join up with other beings of similar interests.  Immature adults seeking thrills sometimes become ensnared by dark forces, or might even seek them out; they also are likely to join up in quests to destroy said forces.  Their need for gold (and their magical powers in general) are weaker during this phase of their life, limiting their need for gold exposure (see Culture, below) and thus the need to be tied to a territory and hoard.  Of course, some cautious, pragmatic, or particularly greedy individuals can't wait to get started in their kind's most popular passtime, as it were, and can be found scrounging for gold the moment they leave their mother's nest.
Skyhaven dragons commonly reach sexual maturity sometime between 125 and 150 years, but they don't always select a partner at this time.  With maturity comes an increased desire and need to establish a hoard and home territory, though a dragon who is willing to sacrifice magical potency can ignore these instincts to a degree.  If and when they do decide to settle down, dragons often mate for life, but this is not a hard-and-fast rule.  Much like humans, dragon loyalty between mates is not always eternally binding.  Some change partners as often as the seasons change, while others never take a mate at all.  Females only lay clutches of eggs every fifty years, an adaptation to their long lifespan and few predators.
Western dragons grow throughout their lives, but after their one thousanth year the growth rate is virtually undetectable.  Skyhaven dragons generally live only for about 2000 to 3000 years.

Culture
Like dragons themselves, dragon culture is very hard to generalize.  Though they usually have solitary lairs, they often form communities with other nearby dragons or sentient creatures (usually excluding humans), such as griffins.  Within a community, social hierarchy is loose, but often one individual will emerge as the "king" or "queen" of a particular area; it is to them that the others turn to settle disputes or help organize themselves in the event of danger.  Dragons do not historically cooperate by instinct under pressure, however, so the title tends to hold little weight in a true crisis.  A dragon who has the power to actually command their fellow dragons is very rare, and thus often revered.
Most "Western" dragons must have some sort of hoard, and ideally a method of increasing it over time.  Gold is not only a comfortable bedding material (for a dragon, at any rate), but the mineral enhances their magical energies.  Being a magical being, this is essential.  Lying on a bed of gold increases their healing rate, brings restful sleep, and can inspire powerful, even prophetic dreams.  Their hoards are rarely limited to just one element, though; dragons collect all sorts of beautiful things, often with little regard for outside worth.  The size and variety of a dragon's hoard acts as a status indicator, though gold always dominates.

Temperament
Dragons, like all sentient beings, vary widely in temper, but many have a touch of ego and a hot temper (no pun intended).  Skyhaven dragons can live on their own or adapt to small groups, and will usually get along with other residents of their land, but they are still dragons, and as such deserve a certain amount of respect and privacy.  It is best not to try their patience.  Two of the surest ways to do that are to attempt to confine them or to enter their lair unbidden.  Remember, defending their hoard is not simply a matter of greed, but a matter of well-being and survival; dragons without access to gold bedding will die from gold energy deprivation.  They have learned to be wary of outsiders to whom gold is no more than another shiny object, a means to an end, or a simple obsession.
One common failing of dragons, especially older dragons, is greed.  The urge to increase their hoard is very strong, and they often think themselves the better of other beings who challenge them in games of riddle or chance.  Challenging a dragon should never be done lightly, as they are indeed rather clever and perhaps a bit more lucky than pure chance might explain.  Though most dragons will honor a loss (if very angrily and reluctantly), beware the unscrupulous loser, especially if you happen to be flammable or edible.

Magical Traits
Many Western dragons can "breathe" fire, or more accurately spit fire.  They have a magical substance known as fireblood in their bodies, which helps them maintain internal temperature (being reptiles, this can be a problem) and achieve flight by adjusting their buoyancy.  It flows through their veins but, like oil and water, fireblood and true blood never mix, though neither interferes with the others' functions.  The firelung, also called a fire heart, is a uniquely draconic organ that concentrates and distributes the substance into the bloodstream, filtering it out of the veins and pushing it back into the arteries, acting as both heart and lung to the fireblood.  It exists just below and behind the true heart and lungs, surrounding both with specialized filtering vessels.  No fireblood enters the blood-pumping heart (whose turbulence might trigger an adverse incendiary reaction) or true lungs (lest the fireblood ignite on contact with air), and no true blood enters the firelung.  At the back of a dragon's throat are two openings connected to muscular sacs filled by the firelung.  Through these, the dragon can spit streams of fireblood, much like a spitting cobra can spit poison through their fangs or a horned toad can squirt blood from its tear ducts.   Upon hitting open air, the fireblood ignites into the characteristic defense mechanism of the Western dragon.  This results in a ball or stream of fire with a semi-liquid core which can stick to victims until consumed by flame, similar to napalm.  The flame shape, temperature, and color varies by species and mood.  Fury-induced flames burn hotter and brighter than teasing blasts.   Dragons are highly resistant to burns, and their saliva gives added protection to their mouth.  Because they usually use a blast of air to enhance the flames and propel the burning fireblood outward more forcefully, the misconception that the fire was coming from the dragon's true lungs arose.  Actually, the lungs are vulnerable to fire, and a dragon who actually does inhale open flames (very rare, due to physical adaptations) will die. When a dragon is cut or stabbed, the exposed fireblood cauterizes and disinfects the wound instantly, usually burning whoever or whatever caused the cut in the process.
Also noteworthy is the effect of a dragon's hoard on the dragon itself.  Because they absorb energies from the gold and other substances, they can also absorb blessings or curses from hoard objects.  "Evil" dragons who go on fiery rampages, develop a gruesome taste for sentient beings, or otherwise behave irrationally are often victims of cursed items in their hoards.  Heroes who, after slaying said dragons, succumb to cruel fates are also often the victims of the same items, having confiscated the hoards for themselves without bothering to have the contents checked out by a competent mage.  On the other hand, blessed items in a dragon's hoard can have quite the opposite effect, transforming a dragon into a near-divine being capable of great healing and oracular advice.  Dragons themselves have stron enough energy auras that they often don't recognize a curse or a blessing unless it is particularly powerful (the equivalent of trying to see the light of a candle in a sunlit room), which is how tainted items end up in hoards to begin with.
While many Western dragons are reasonably talented shapeshifters, the Skyhaven dragon, alas, is not one of them.  The best they can usually manage is making themselves bigger or smaller, and some few can assume a vaguely bipedal shape.

Other Notes
As noted in many stories and legends, dragons are capable of speaking any human tongue (and most inhuman ones as well), and are very quick students of written languages.  The native dragon tongue sounds to most beings like a mixture of growls and hisses with a vaguely harmonic resonance, a language very few non-draconic beings ever learn to speak fluently, or even competently.  Considering how similar many dragon curses and compliments sound to the untrained ear, practicing should only be attempted within earshot of particularly understanding dragons.