A humanoid skull shrouded in black necrotic energy, perfectly preserved. 

Sentience. Zeff's black skull is a sentient chaotic neutral item with an Intelligence of 20, a Wisdom of 22, and a Charisma of 16. It has hearing and darkvision out to a range of 60 feet.

The skull communicates telepathically with its wielder and can speak, read, and understand Dwarvish, Vedalken, Abyssal, Celestial, Draconic and Common.

Personality. A human named Zeff lives within the skull. The item yearns for more knowledge. Trying to push the wielder for more knowledge and a mutual interest in the arcane nature of the world.

Dormant

The skull grants the following benefits in its dormant state:

• You can speak, read, and write Dwarvish, Vedalken, Abyssal, Celestial and Draconic.
• You gain a +1 bonus to your spell-casting ability modifier 
• You gain advantage in your Investigation(Int) and Arcana(Int) checks when trying to study new things.

 Awakened

The skull grants the following benefits in its awakened state:

• The bonus to your spell-casting ability modifier increases to +2.
• While attuned to this item you may use your action to activate Zeff's Draconic Eyes. While active, you can see the aura of magical items and objects. Unlike the Detect Magic you can't discern the school of magic, but you can still see a faint outline on any magical object, item, or active spell. You'll also be able to see outlines of hidden passages like you would if you had truesight. This feature can only be used once per short rest and lasts for 10 minutes.

ARTIFACT PROPERTIES

Random Properties. The artifact has the following randomly determined properties:

• While attuned to the artifact, you can use an action to cast Speak with Dead from it. After you cast the spell, roll a d6. On a roll of 1–5, you can’t cast it again until the next dawn.
• While attuned to the artifact, you gain a +1 bonus to Armor Class.
• While attuned to the artifact, you deal 1d6 necrotic damage to any plant you touch that isn’t a creature.
• While attuned to the artifact, you are deafened when you are more than 10 feet away from it.

Notes: Language: Abyssal, Bonus: Spell Save DC, Bonus: Spell Attacks, Language: Celestial, Language: Dwarvish, Language: Vedalken, Language: Draconic, Advantage: Investigation, Advantage: Arcana, Bonus: Armor Class, spellcaster