X the Mystic's Arcane Grimoire

X the Mystic's Arcane Grimoire was a powerful spellbook presumably written by "X the Mystic" that was discovered in the Tomb of the Nine Gods in Chult in the late 15 century DR.

Description
It had its title burned into its binding.

Owner
The Arcane Grimoire was in the possession of the arcanaloth Ygga Raxyg in the lowest levels of the Tomb of the Nine Gods.

Powers
The Arcane Grimoire had one to three extremely powerful spells, some of which could even equal Acererak's own magical powers.

Appearances

 * Adventures:
 * Tomb of Annihilation