Source: Tales from the Yawning Portal

Weapon (greatsword), legendary (requires attunement)

Waythe is a unique greatsword most recently in the possession of a high-ranking cloud giant ambassador.

You gain a +1 bonus to attack and damage rolls made with this magic weapon. When you hit a creature of the giant type with it, the giant takes an extra 2d6 slashing damage, and it must succeed on a DC 15 Strength saving throw or fall prone.

The sword also functions as a Wand of Enemy Detecetion. It regains all of its expended charges at dawn and isn't at risk of crumbling if its last charge is used.

Sentience. Waythe is a sentient weapon of neutral good alignment, with an Intelligence of 12, a Wisdom of 2, and a Charisma of 14. It has hearing and darkvision out to a range of 120 feet.

The weapon can speak and understand Giant and Common, and it can communicate telepathically with its wielder.

Personality. This sword believes in freedom and allowing others to live as they see fit. It is protective of its friends, and wants to be friends with a like-minded wielder. (It takes only 1 minute for a good-aligned character to gain attunement with the sword.) Waythe is courageous to the point of foolhardiness, however, and vocally urges bold action. It is likely to come into conflict with an evil or a timid wielder.