The third arc revolves around this prophecy, which was revealed on April 26th, 2018. It was delivered by Moonwatcher to Luna, though she may have first had the vision during the events of Darkness of Dragons.
Turn your eyes, your wings, your fire
To the land across the sea
Where dragons are poisoned and dragons are dying
And no one can ever be free.
A secret lurks inside their eggs.
A secret hides within their book.
A secret buried far below
May save those brave enough to look.
Open your hearts, your minds, your wings
To the dragons who flee from the Hive.
Face a great evil with talons united
Or none of the tribes will survive.
These are user interpretations of her prophecies, and while they have been reviewed and deemed accurate by parts of the community, it is important to note that they are not stated in canon.
To the land across the sea refers to Pantala.
And dragons are dying may be a reference to the LeafWings in the Poison Jungle, who lose a few dragons each year to carnivorous plants. However, it could also refer to the future deaths that may occur now that the othermind can gain control of SilkWings and LeafWings.
And no one can ever be free most likely refers to the HiveWings under Wasp's mind control, the SilkWings under Wasp's rule, and the LeafWings being unable to leave the Poison Jungle.
A secret lurks inside their eggs is a reference to Queen Wasp poisoning HiveWing eggs with the breath of evil.
A secret hides within their book refers to the map showing how to fly to Pyrrhia, hidden in the binding of the Book of Clearsight. It could additionally refer to the fact that no predictions from the book are relevant to the present day.
A secret buried far below refers to the scavenger city around the abyss, or, the fact that Raven's friend's older brother, Vole, was (most likely) being mind controlled by the Othermind. It could also be either the fact that the Pantalan scavengers might know something about the abyss, or that the Othermind can also control scavengers as well.
May save those brave enough to look refers to everyone who has the courage to stand up to Queen Wasp and the othermind.
Open your hearts, your minds, your wings is probably a reference to what appears to be the theme of this arc: empathy versus resistance to evil. Opening your heart means empathy, which is one of Blue's strengths; opening your mind means discovering and accepting the truth, Cricket's power; and opening your wings means resisting and fighting back, which Sundew is known for. All the point-of-view characters seem to be gradually discovering that they need all three of these to carry out a revolution. For example, Blue was very empathetic but rather ignorant and passive at the beginning of The Lost Continent but has since opened up his mind and wings, and Sundew has learned to open her heart and be empathetic to the HiveWings and SilkWings who might not like Wasp and who she previously believed to be evil and cowardly. (However, this could be meant to persuade Snowfall to be more open-minded to the Pantalan dragons who aren't controlled by the breath of evil.)
To the dragons who flee from the Hive refers to the dragons who escaped Pantala before being controlled by the othermind.
Face a great evil with talons united foreshadows that dragons of all tribes will be forced to put aside their differences to defeat the othermind.
Or none of the tribes will survive probably predicts that the othermind will eventually spread to Pyrrhia unless stopped.