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This book was given to me when I was your age, but I have a feeling it will be of more use to you than it was to me.
Gaius to Merlin[src]

Gaius' Grimoire is a book of magical knowledge. It was originally owned by Gaius, who later passed it down to his apprentice Merlin.


Gaius was given his grimoire when he was still a young man. After magic was outlawed during the Great Purge, Gaius kept the book hidden and later gave it to Merlin after he became Arthur's manservant (The Dragon's Call).

Merlin used an animation spell recorded in the grimoire to bring a statue of a dog and the snakes on Valiant's shield to life (Valiant).

When Camelot was stricken by a magical plague, Arthur nearly discovered the book during his door to door search for evidence of sorcery. Merlin later used a healing spell recorded in the grimoire to cure Guinevere's father with a magic poultice (The Mark of Nimueh).

Merlin used an enchantment recorded in the book to help kill the Griffin terrorizing Camelot (Lancelot).

After Arthur was bitten by the Questing Beast, Merlin tried using two spells recorded in the book to heal him, but they had no effect (Le Morte d'Arthur).

After learning that Uther had sent for the Witchfinder to investigate evidence of sorcery, Gaius told Merlin to make sure the book was hidden (The Witchfinder).

Merlin tried to use several spells recorded in the grimoire to wake Gaius from his enchanted slumber, but none of them had the desired effect (The Fires of Idirsholas).

When Gwen was accused of enchanting Arthur with a love spell, Merlin used an ageing spell recorded in the grimoire to pose as Dragoon the Great and prove her innocence (Queen of Hearts).

After Morgause, Morgana, and their immortal army conquered Camelot, Merlin took the book and the Avalon Vial from his room before escaping (The Coming of Arthur).


Series 1
The Dragon's Call
The Mark of Nimueh
Le Morte d'Arthur
Series 2
The Witchfinder (Mentioned only)
The Fires of Idirsholas
Series 3
Queen of Hearts
The Coming of Arthur


  • Merlin learnt most of the spells he mastered from this grimoire.
  • Gaius was given the grimoire when he was Merlin's age (The Dragon's Call).
  • It is unknown how much of the book's contents were discovered or developed by Gaius and how much came from other sources.


To view the Gaius' Grimoire gallery, click here.

See Also[]