Howl of the Wind Dragon: A Branches Book (Dragon Masters #20)

The wizard Astrid is planning to cast the False Life spell which will bring to life the bones of giant ancient beasts and allow her to conquer all the kingdoms; in order to prevent her the Dragon Masters must find the Wind Dragon, the final dragon needed to undo the spell--but that dragon and her Dragon Master are captives, and it is up to Drake and his friends to rescue them, and hope they are in time to stop Astrid.