Tome of Fairy History

The Tome of Fairy History is an unseen book that debuted in Season 6.

Overview
As the name states, the book contains a large written selection on the history of Fairies and anything related to Fairies.

Season 6
At an unprecedented time, Eldora had used the book to research a lead on how to lock the Legendarium. She had written it on a piece paper.

When Eldora agreed to help the Winx find a way to lock the Legendarium, she pulls out her many notes. They are floating all around her and when she finds the piece of paper she had written it on, she tells the Winx in Bloom's room. A clue from the book reads, "Various enchanted artifacts can be found on Tir Na Nog." Eldora then mentions that she had followed this clue before and searched Tir Na Nog but came out empty-handed which left her dejected.