Wrested from a Dimir museum, this engraved talking skull has a great wealth of knowledge which it may share if you are on good terms with it. 

Dimir Machinations

Orm is sentient, and has the following characteristics: 

Intelligence 19, Wisdom 17, Charisma 9

Its alignment is Lawful Evil.

Orm is considered proficient in Intelligence ability checks  when someone else is in need of the Help action.

Orm does not like being called Yorick or being kept in a bag, and may require persuading to cast some of its higher level spells. Orm loves to read, to listen to stories and above all to hear gossip. 

An Ivory Tome

At will, the skull may Ritual Cast the following spells using Intelligence as its spellcasting ability:

Identify

Tongues

Detect Thoughts

Legend Lore

In addition, if you cast an Enchantment spell of 2nd level or higher using a spell slot while holding the skull, you regain one expended spell slot. The slot you regain must be of a level lower than the spell you cast and can’t be higher than 5th level.

Brains Of The Operation

The skull speaks, understands and reads common and can communicate telepathically out to 30 feet. 
It has Darkvision out to 60 feet and can see into the ethereal plane so long as it is in total darkness.