Weapon (longsword), artifact (requires attunement by a good aligned Divine Fae)

This is the divine sword of the elder goddess, Danu, and it is blessed by her celestial power. For nearly two millennia, creatures of the mortal realm have thought this blade was a legend. They were wrong. They have forgotten that Danu used this sword against the ancient Titans and Cyclops during the War of the Divine before the Great Freeze claimed the world. There are few who know of this blade's true existence and where it resided for more than 20,000 years in the Old Forest of Tír na nÓg. Many have quested to find it over the course of the last two millennia after the Great Freeze began to subside, searching every hidden corner of Gaea, mostly those who want to use it for their own reasons and do very cruel things (e.g., over tax, take other people's women, kill those who annoy them, etc.). Those who went questing for it sought it for the incredible power that it could grant them. But only those who are truly worthy could even find the blade, and of those, only an incredibly elite few might ever be found worthy of drawing it from its eternal scabbard of stone. Only a handful of the Clerics of Danu have been gifted with the knowledge of its resting place and they have guarded it with their very lives for the last 1,000 millennia.

The sword is crafted from the pure alicorn of the first unicorn collected at the moment of its natural death. The golden crossbar radiates with a divine glow evidencing its power. The emerald hilt contains a portion of Danu's divine power while the pommel is crafted of the finest gold colored adamantium and is shaped to look like the head and alicorn of the great unicorn, Alairia, from whom the sword was crafted. In the mortal realm, the Sword of Danu appears to be just an ordinary, yet exquisitely crafted, mundane longsword; but in Tír na nÓg or when its command word is spoken during combat, the sword reveals its true divine appearance.

Dormant. When the command word "Cumhacht Danú" is spoken to activate the sword's power, you gain a +1 bonus to attack and damage rolls made with this magic weapon. Once per round, when you hit with an attack made using the Sword of Danu, you can cause the target to take 2d6 radiant damage. If the target is a monstrosity, fiend, or undead, it takes 4d6 radiant damage instead.

Awakened. When the command word "Cumhacht Danú" is spoken to activate the sword's power, you gain a +2 bonus to attack and damage rolls made with this magic weapon, and the sword's property now deals 4d6 radiant damage, increased to 6d6 against monstrosities, fiends, and undead.

• Leader's Charge. As a reaction, when you or an ally within 60 feet of you makes a saving throw against the charmed or frightened condition, it makes that save with advantage and gains 25 temporary hit points on a success.

Exalted. The sword no longer needs to be activated as it permanently retains its divine appearance. You gain a +3 bonus to attack and damage rolls made with this magic weapon, and the sword's property now deals 6d6 radiant damage, increased to 8d6 against monstrosities, fiends, and undead.

• Call of Danu's Might. As an action, you can raise the Sword of Danu high and call forth the spirits of six loyal Fae knights. The called knights appear in unoccupied spaces within 60 feet of you, use the knight statistics, and disappear after 3 hours or when they are reduced to 0 hit points. The Sword of Danu can't be used this way again until the next dawn.

Proficiency with a Longsword allows you to add your proficiency bonus to the attack roll for any attack you make with it.

This weapon has the following mastery property. To use this property, you must have a feature that lets you use it.

Sap. If you hit a creature with this weapon, that creature has Disadvantage on its next attack roll before the start of your next turn.