The elder dragons

The oldest and most potent are the elder dragons (or The dragons of ...), who are powerful enough to destroy a kingdom single-handedly.
There are 6 known elder dragons:

• The elder dragon of fire (location: Palma)
• The elder dragon of air (location: unknown)
• The elder dragon of water (location: unknown)
• The elder dragon of Ice (location: unknown)
• The elder dragon of nature (location: unknown)
• The elder dragon of mind and soul (location: Xendir)

(most of their info comes from documents, eyewitnesses, and the elder dragon of mind and soul)