Weapon (greatsword) , Legendary (unique)
+2 aberration bane greatsword (requires attunement)
When you hit an aberration with it, the aberration takes an extra 2d6 damage of the weapon’s type and must succeed on a DC 15 Intelligence saving throw or be Frightened until the end of its next turn. For the purpose of this weapon, “aberration” refers to any creature with the aberration type, including aboleths and illithids.
While wielding the weapon, the bearer has resistance to psychic damage.
When you attack a creature with this magic weapon and roll a 19 or 20 on the attack roll, that target takes an extra 10 necrotic damage if it isn't a construct or an undead. You also gain 10 temporary hit points. This affect also occurs if you strike a killing blow on a creature.
Once per short rest you may cast the spell "Armor of the Altraloth"