Source: Bigby Presents - Glory of the Giants

Wondrous Item, Legendary (Requires Attunement)

This golden harp is sculpted in the image of the god Iallanis, depicted as a young cloud giant woman. When a creature comes within 5 feet of the harp, the instrument animates and is capable of speaking, singing, and playing by itself.

Whenever you attempt to attune to the harp, you must first make either a DC 15 Charisma (Performance) check or a DC 20 Charisma (Persuasion) check to convince the harp that you are worthy, attuning to the harp on a success. If you fail, you can’t attempt to attune to the harp again until the next dawn. Once you have successfully attuned to the harp, the harp resizes to suit you.

Stalwart Song. Whenever you make a Charisma check while attuned to the harp, you can treat a roll of 9 or lower on the die as a 10.

Feast of Plenty. If you spend 10 minutes playing the harp, you can cast the Heroes' Feast spell from it. Once this property is used, it can’t be used again until 1d10 + 10 days have passed.

Soothing Melody. As an action, you can use the harp to cast the Calm Emotions spell (save DC 19). When the spell is cast using the harp, its duration increases to 1 hour, provided you maintain concentration on the spell. This property can be used five times, and it regains all uses at dawn.

Sentience. The harp is a sentient, chaotic good object with an Intelligence of 13, a Wisdom of 15, and a Charisma of 20. It has hearing and darkvision to a range of 120 feet.

The harp can speak, read, and understand Common and Giant. It can also communicate telepathically with the creature attuned to it.

The harp has a dramatic and pompous personality, taking extreme pride in the quality of music produced from its strings. If the harp is shorter than 6 feet tall, it bemoans its height.