Zikran's Zephyrean Tome once a prison for a Djinni named Gazre-Azam, now can be used to summon him once per long rest.

This Tome give you access to the Find Familiar spell. However you can only use this spell to summon the Djinni Gazre-Azam. He uses the stat block of a regular Djinni.

This spellbook, along with anything written on its pages, can’t be damaged by fire or immersion in water. In addition, the spellbook doesn’t deteriorate with age. 

Notes: Summoning, Sentient