Titanoboa Glaive Vipa

Melee weapon (Martial, Halberd), Artifact, Requires Attunement

Damage: 1d10
Damage Type: Slashing
Properties: Heavy, Reach, Two-Handed

“This deadly glaive is the signature weapon of Bai Suzhen, the White Snake Witch. This cosmic entity is a sorceress of the highest order, and seeks to enforce her rule on the universe.

Made from the fossilized remains of the Titanaboa, an ancient serpent known for its immense size and endless hunger. The glaive is crafted from it’s incredibly flexible spine allowing its wielder to put incredible force behind each of it’s vicious blows.

This weapon seems incredibly similar to the weapons of the other great beasts but if they were meant as a way for ancient mortals to defend themselves from her forces… How does she have one? What does this mean for the grander implications of this narrative?”

Heavy - Small creatures have disadvantage on attack rolls with heavy weapons. A heavy weapon’s size and bulk make it too large for a Small creature to use effectively.

Reach - This weapon adds 5 feet to your reach when you attack with it, as well as when determining your reach for opportunity attacks with it. 

Two-Handed - This weapon requires two hands when you attack with it.

You gain a +2 bonus to Attack and Damage rolls with this magical weapon. Additionally, when you successfully deal damage to a creature with this weapon, it must make a DC18 Constitution saving throw or be Poisoned. When Poisoned in this way, the effect can only be removed with a spell that ends the Condition or a Long Rest. 

Serpent’s Tongue - While attuned to this weapon, you gain Advantage on all Deception, Intimidation, and Persuasion checks. 

The Best Medicine - While attuned to this weapon, you are immune to Poison damage and the Poisoned condition. Additionally, you can use an action to touch a Poisoned creature and magically end the condition. 

Make My Glaive Grow! - As an Action you may hurl the Glaive into the ground, causing it to transform and unleash the shade of the spirit trapped within. See the Titanboa Spirit below. This creature takes its turn directly after you and follows all orders. If it is not given orders, it takes the Dodge action.

If you or the Titanoboa Spirits are ever Unconscious, the weapon reverts back to its normal form. 

Titanoboa Spirit

Huge Beast, Unaligned

AC 16 (natural armor)
HP 123 (13d12+39)
Speed 30 ft., Swim 30 ft. 

STR 19 (4)  DEX 12 (1)  CON 17 (3)  INT 1 (-5)  WIS 12 (1)  CHA 4 (-3) 

Saving Throws: Strength +7
Skills: Perception +4, Stealth +4
Damage Immunities: Poison, Psychic
Condition Immunities: Charmed, Frightened, Poisoned 
Senses: Blindsight 20ft. Passive Perception 14
CR: 7 

ABILITIES

Magic Resistance - The Titanoboa Spirit has advantage on saving throws against spells and other magical effects.

Actions

Multiattack - The Titanoboa Spirit makes one Constrict attack and two Bite attacks. 

Constrict - Melee Weapon Attack: +7 to hit, reach 20 ft., one creature. Hit: 22 (4d8 + 4) bludgeoning damage. If the target is Large or smaller, it is grappled (escape DC 15). Until this grapple ends, the target is restrained, and the Titanoboa Spirit can't constrict another target. At the start of a creature’s turn, if it is restrained by this ability, it takes 22 (4d8 + 4) Bludgeoning damage. 

Bite - Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 15 (2d10 + 4) piercing damage.