Hundreds of years ago, Lysanthir, an elven bladesinger of almost demigod-like power, forged for himself an immensely powerful sword, which further enhanced his already-great prowess. His power was great enough that when he finally fell in battle - battling a demon lord and his horde of minions - he was able to transfer his consciousness into the sword, as well as some of his magical capabilities. Even though its original powers have faded with the ages, because of this transferal, the blade is capable of flying and of using enchantment magic, and so it became known as the Mageblade. However, the essence of the demon lord Lysanthir was combating also transferred to the sword, corrupting Lysanthir's mind and soul. Over the centuries, what was left of Lysanthir's mind became ever more twisted and dark - almost alien. It is known to charm unsuspecting people, gaining control over their minds before brutally slaying them.

You have a +3 bonus to attack and damage rolls made with this magic sword. It deals an additional 2d8 slashing damage to elves, and it functions as a dancing longsword. When you score a critical hit with the Mageblade, triple the number of damage dice instead of doubling it.

Random Properties. The Mageblade has the following random properties:

• 2 minor beneficial properties
• 1 major beneficial property
• 2 minor detrimental properties

Charm. You can use your action to attempt to charm one creature within 60 feet of you. Unless the creature has an Intelligence lower than 4, it must make a Wisdom saving throw (DC 19) or be charmed by you for 10 minutes. Whenever the creature takes damage, it can repeat the saving throw, ending the effect on itself on a success. Any creature charmed in this way has its speed reduced to 0, and any time you hit a creature charmed in this way with an attack with the Mageblade, you automatically score a critical hit. Once you have used this property three times, it cannot be used again until the next dawn.

Corrupting Attunement. As you remain attuned to the Mageblade, its corrupting influence changes you to become more like it. When you attune to it, and at dawn every 7 days afterward that you remain attuned to it, you must succeed on a DC 15 Charisma saving throw or have your alignment changed one step toward chaotic evil. As you fail these saving throws, your alignment first changes from lawful to neutral to chaotic, then from good to neutral to evil. For example, if your alignment is neutral good, it would shift to chaotic good, then to chaotic neutral, then to chaotic evil. A remove curse spell reverses this change by one degree (from evil to neutral to good, then from chaotic to neutral to lawful) until your alignment is restored back to what it originally was. In the same way, a greater restoration spell reverses the change by up to two degrees, and a wish spell or divine intervention can fully restore your original alignment. If the Mageblade is destroyed, the sword's change to your alignment is reversed by one degree every thirty days until your original alignment is restored.

Sentience. The Mageblade is a sentient chaotic evil weapon with an Intelligence of 18, a Wisdom of 12, and a Charisma of 16. 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 Elvish. Its voice changes randomly between the clear, ringing voice of an elf and a demon's monstrous rasp.

While no creature is attuned to the Mageblade, it gains full control over itself and its movement and becomes an NPC under the DM's control, using the Mageblade statblock.

Personality. The Mageblade has virtually no purpose other than to destroy. It demands that it be used to slay at least one creature (with an Intelligence score higher than 5) each day. If three days pass without this condition being met, a conflict arises between the Mageblade and its wielder, as described in the Dungeon Master's Guide.

The Mageblade also has a bitter loathing of elves, and so no elf can attune to it. If it comes within 120 feet of an elf, the sword flies into a rage that can only be calmed by removing the elf from the Mageblade's sight or the elf's death. While an elf remains within 120 feet of the sword, its wielder has disadvantage on attack rolls against any creature that is not an elf aw well as advantage on attacks against elves.

Destroying the Mageblade. Though the magic required is far beyond the level of magic wielded by any normal spellcaster, even amazingly powerful ones, legend tells of a way to destroy the legendary sword that houses what is left of Lysanthir's corrupted soul. The fabled Forge of Worlds, where many artifacts were forged, is the only place where the Mageblade may be destroyed. It is hidden far underground, far beneath the lowest reaches of the Underdark, and finding information leading to the Forge's location could take decades.

The process requires the expenditure of a massive amount of magical energy - specifically, the 24 hour ritual requires seven main spellcasters, each of whom must expend a 9th-level spell slot, as well as at least fifty lesser spellcasters, who must expend spell slots whose total level equals or exceeds 100. At the end of each ritual, one of the main spellcasters must succeed on a DC 20 Intelligence (Arcana) check, or that instance of the ritual fails. The ritual must be repeated every 10 days for 1 year, or the attempt fails and the entire process must be restarted. For the entire year, the Mageblade must be continually heated by the flames of the Forge of Worlds.

If all the rituals are performed successfully, the Mageblade is destroyed in a burst of arcane energy, instantly destroying everyone and everything (except the Forge of Worlds and any other artifacts) within 10 feet of it and dealing 20d6 force damage and 20d6 fire damage to all creatures and objects within 120 feet of the Mageblade. Lysanthir and the demon lord's souls are destroyed with the sword.

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

Notes: Damage: Slashing, Bonus: Magic, Charmed, Versatile, Sap