The Guardian Stone is a mystical gem located in North's Workshop.
The Guardian Stone is only used when the Man in the Moon is choosing a new guardian. The gem used the Man in the Moon's moonlight to refract the light and created a spectrum of the new Guardian.
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related to Guardian Stone.
- The gem is located in North's Workshop under a floor design that can only be open by the Man in the Moon's moonlight.
- In The Art of Rise of the Guardians, a sketch of the "Altar Design" reveals that the stone is made out of moon rock, indicating the stone was a gift from The Man in the Moon, containing part of itself (in the film, MiM is a spiritual deity), so that is can directly make contact with the Guardians.