One of the five ancient tomes authored by Zet, an ancient draconic deity of forbidden knowledge. The book is bound in black dragon-scale leather and is imbued with conjuration magic.

When attuned to the book, you gain resistance to Acid damage. Once per day, you can use the Black Tome to cast the find familiar spell. When you use the Black Tome to cast this spell, you can choose to summon a black pseudodragon as your familiar, using the pseudodragon familiar variant in the Monster Manual. If you become unattuned to the Black Tome, any summoned familiar disappears

You can also use an action to summon an amphiptere, a draconic creature with no arms or legs, dripping with darkness. It manifests in an unoccupied space that you can see within 30 ft., from a dark void that echoes a cacophony of maddening laughter and screams. This corporeal form uses the stat block below. The amphiptere is summoned for 1 hour, and you must maintain concentration on it as you would for a spell. The creature disappears when it drops to 0 hit points, after 1 hour, or if you lose concentration on the amphiptere. When the creature disappears, it falls to the ground and dissolves, withering the plant life it landed on and leaving behind any items it was carrying.

The creature is an ally to you and your companions. In combat, the creature shares your initiative count, but it takes its turn immediately after yours. It obeys your verbal commands (no action required by you). If you don’t issue any, it takes the Dodge action and uses its move to avoid danger.

Once the shadow amphiptere has been summoned, it cannot be summoned again for 1d6 days.

Mount. The shadow amphiptere is capable of bearing one humanoid creature on its back while flying.

Wreathed in Shadow. The shadow amphiptere has advantage on stealth checks in dim light and is imperceptible to all creatures without darkvision, blindsight, or truesight while in darkness.

Actions

Multiattack. The shadow amphiptere makes 2 bite attacks

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 7 (1d6+4) piercing damage and 3 (1d6) necrotic damage.

Shadow Breath (recharge 6). The shadow amphiptere exhales necrotic ooze in a 30-foot cone. Each creature in that area must make a DC 14 Constitution saving throw. A creature takes 5d6 damage necrotic on a failed save, or half as much damage on a successful one.