The origin of dragons.

Eggs

Thought mine would be funnier. It's probably the first one. Would be funnier if it was the ignorant savages who were right though. "Told you! Moon Egg.*As Second Moon Breaks up and fills the planet with Flying Spiders who breath boiling acid*"

That was my thought originally except it's not magical, kind of a let down that the in universe answer would be "They were just there" and Valys are already super legends in the world, them making dragons is just more to pile onto them.

@sinstar: It could still be magical. We don't actually know the origin of the AGOT universe, nor do we know how magic came to exist in the world. Maybe the world came into being, the dragons were just oversized wyverns but a magical pulse explosion created them. Maybe they just liked to eat a bunch of phosphoric rocks and got really bad indigestion and now burp fire (Dragonriders of Pern cough)

Where did the Children of the Forest come from?
Where did the White Walkers come from? << Not the stupid stupid creation in the tv show.
What magical creatures are tied to the other elements? What are all of the other elements? Of the primal elements above we have 3 of 5 (Earth, Fire, Water)

magnus: Are the Dragons themselves making magic stronger by existing? Or do they exist because magic is stronger?

So what if the children and white walkers are "people". There is no rule that says a magical creature must be some massive element breathing weapon of war or anything. Having a species that is manlike and a magical creature is pretty standard for fantasy series.

Saying a dragon has always been there isn't a meh explanation either. It means that they are older or similarly aged to humans. Comparison: Where did the moon come from in AGOT? It's always been there. Sure they could be like "During the formation solar system, the larger particles began collecting together and pulling their neighbors in until they started forming a planet, however perhaps a collision ejected some of the material off the main body which then took shape to form a secondary smaller satellite body".

If the dragons came from a "Second moon" Why doesn't everyone know about the second moons existence?

And where exactly is the question about lore coming from exactly? I mean if we wanna go with "lore", Planetos is just a spec in a giants eye.

Also, depends how long ago the second moon egg hatched. Could be the pieces coalesced into the normal moon or crashed into the planet. Maybe aliens came by and stole the pieces for research. Maybe the lord of light is just an ancient chinese dragon that is one of the original 7 dragons and is a borderline divine being who rules over the americas continent full of japanese-aztec people and has the ability to influence the realm at west with sufficiently powerful blood sacrifice full of divine luck that is demonstrated by ones ability to rise and hold positions of power in the rather deadly game of thrones.

On topic however, dragons being a naturally occur creature with either magic fire or bladders filled with either a gasous or liquid flamable they puke out and ignite with hardened plates in their mouth could work, with fire resistance being their natural state from developing near volcanoes. Could very well be some divine being placed them there at creation just to see how the other creatures ran in terror and then panic'd when his praactical joke turned into valyrian weapons of war and he decided "Nope!" and super volcano'd the mistake away. Basically, not enough info to really give any justifiable theories our side. Since the sources in lore seem to be very big on the idea of the unreliable narrator given how it always specifies an in lore character for the theories.