Lash of Shadows

From Explorer's Guide to Wildemount, page 276.

Description
Weapon (whip), artifact (requires attunement).

This snakeskin whip is touched by the power of Zehir and ends in five animated serpent heads.

Sentience. The Lash of Shadows is a sentient chaotic evil weapon with an Intelligence of 18, a Wisdom of 16, and a Charisma of 20. It has hearing and darkvision out to a range of 120 feet.

The weapon communicates telepathically with its wielder and can speak, read, and understand Abyssal, Common, and Draconic.

Personality. A mad marilith named Sizlifeth lives within the Lash of Shadows. The weapon has a short temper and experiences only extreme emotions. It is most happy when dealing harm.

Dormant. The whip grants the following benefits in its dormant state:
 * The whip has one minor beneficial property and one minor detrimental property.
 * You can speak, read, and write Abyssal and Draconic.
 * You gain a +1 bonus to attack and damage rolls made with this magic weapon.
 * You can attempt to poison any creature that is hit by the whip. The creature must succeed on a DC 13 Constitution saving throw or suffer the effect of one of the following poisons of your choice; once a poison other than Serpent Venom has been used, that poison can't be used again until the next dawn:
 * Dead Eyes. A creature that fails the saving throw against this poison is poisoned for 1 hour. While poisoned in this way, the creature is blinded.
 * Serpent Venom. A creature that fails the saving throw against this poison takes 3d6 poison damage, or half as much damage on a successful save.

Awakened. When the whip reaches an awakened state, it gains the following properties:
 * The whip gains an additional minor beneficial property and an additional minor detrimental property.
 * The weapon's bonus to attack and damage rolls increases to +2.
 * The saving throw DC for the weapon's poisons increases to 15.
 * The weapon gains a new poison option called Ghoul's Blood. A creature that fails the saving throw against this poison is poisoned for 1 minute. While poisoned in this way, the creature is paralyzed. The creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Exalted. When the whip reaches an exalted state, it gains the following properties:
 * The whip gains a major beneficial property.
 * The weapon's bonus to attack and damage rolls increases to +3.
 * The saving throw DC for the weapon's poisons increases to 17.
 * The weapon gains a new poison option called Cockatrice Tears. A creature that fails the saving throw against this poison begins to turn to stone and is restrained. It must repeat the saving throw at the end of its next turn. On a success, the effect ends. On a failure, the creature is petrified for 24 hours.