Scorching

The Scorching is believed to be a period of time in Pyrrhia when the dragon tribes warred and overthrew the Scavengers, who were the dominant life form at that time. However, The Scorching could also be an explanation of the effects of the two extra moons entering the atmosphere. The additional gravity would cause earthquakes, increased volcanic activity, and gargantuan tsunamis for the following weeks. Along with chemicals and ash raining down during this time, there would be mass extinction across the globe. This theory explains why there are so few scavengers and why the shape of Pyrrhia is different than that of any country currently in existence. It is mentioned several times several times throughout the Wings of Fire series, in The Dragonet Prophecy, as well as in Moon Rising.

Dragons seem to use it as a method of measuring time, since they refer to the current year as 5,012 years since the Scorching (5012 AS).

Dragon tribes were formed based on abilities and habitats, such as deserts, mountains, and the sea. Each tribe chose their own queen, thus allowing dragons to get help when they needed it, and making it extremely hard for a scavenger to kill any one dragon.

Centuries later, a scavenger managed to kill Queen Oasis, proving that scavengers could very well still kill dragons. Webs mentioned in Moon Rising that there are many versions of the history of the Scorching and also said it happened about 5,000 years ago. A popular theory is that before the Scorching, scavengers lived like modern humans in the real world. This is based on when Webs described some of the legends as "stories" and "fairy tales".  

Trivia

• Clay once accidentally called the Scorching "The Scalding" in Starflight's dream, much to Starflight's annoyance. A scald is a very hot burn.
• Dragons nowadays use the events of the Scorching to keep track of time. (For example, 5012 years AS)
• The Scorching occurred 5,012 years before the events in Moon Rising, according to Moonwatcher. This would make The Dragonet Prophecy happen roughly 5,009 years after the Scorching.
• It is said by Young Darkstalker's talking scroll, that after The Scorching, Pyrrhia was in a state of almost constant warfare.