Adamantine Haladie

Haladie are double-bladed polearms that rely on the user's dexterity to keep them in constant motion.

Whenever you hit an object with this weapon, the hit is a critical hit.

Special: Whirl. When you are wielding the haladie in two hands, you can use a bonus action to attempt to whirl the weapon. To whirl, make a DC 10 Dexterity check, adding your proficiency bonus if you are proficient with haladie. On a success, you gain a +1 bonus to your AC until the start of your next turn, the whirling blades acting as a barrier against attacks. On a result of 15 or higher, you gain a +2 bonus, instead. On a failure, you deal slashing damage to yourself equal to your proficiency bonus and gain no bonus to your AC from the whirl this turn.

Finesse: When making an attack with a finesse weapon, you use your choice of your Strength or Dexterity modifier for the attack and damage rolls. You must use the same modifier for both rolls.

Two-Handed: This weapon requires two hands to use. This property is relevant only when you attack with the weapon, not when you simply hold it.

Proficiency: martial, haladie Source: Xanathar's Guide to Everything p. 78, Heliana's Guide to Monster Hunting - Part One p. 122