Secrets of the Sages by IE Castellano

The magical adventure continues... Book three of the World In-between series.

Since first stepping through the portal, Berty has always found the Empire mysterious—full of secrets awaiting discovery. Revealing secrets comes with a price, especially magical secrets. His world begins to unravel. Unless Berty exposes the ancient magical secrets the Seven High Sages concealed from history, he could lose everything and everyone he loves.