With this, your voice can reach people far away.
The Whisperweed (ひそひ草, Hisohisou?, lit. whisper grass), also known as Twin Harp, is a recurring key item in the Final Fantasy series. It has the propriety of transmitting sounds to an equal over large distances.
When trying to save the Earth crystal from the Dark Elf, he puts up a magnetic field so that swords and other metal weapons can't be used. When the party finally meets the Dark Elf he easily eliminates the party, but the power of the Whisperweed sends music from the harp Edward is playing to the Whisperweed. This upsets the Dark Elf and ruins his concentration so that he can no longer maintain his magnetic field, allowing Cecil and the party to use their metallic weapons and armor again.
After defeating the Dark Elf, Edward says he was playing an old elven song that was said to greatly upset dark elves. However, in the 3D version, Edward says it was a song he had learned on his travels to ward off evil.
Edward has a piece of whisperweed hidden in Baron Castle to eavesdrop on Cecil. He also uses whisperweed to stay in contact with the people of Damcyan while aboard the Lunar Whale, until they fly out of the plant's range of transmission.
Whisperweed is also a dummied out key item, accessible only via hacking.
Mysterious grass that can transmit sound over long distances.
The Whisperweed is given to Galuf by Xezat upon entering the Barrier Tower. During the operation of destroying the tower, Xezat and the party separate, as the party heads for destroying the antenna at its top, and Xezat descends to the Generator Room, both sides communicate using the Whisperweed.
Unfortunately, after destroying the antenna, Xezat gets trapped inside an overdrive generator room, which causes his death.
Whisperweed is not an item, but is mentioned in the "Whisperweed Blossom" errand:
The labyrinthine cave on the outskirts of Warjilis led to a vast underground lake. We sensed we were being watched as we stared across the water, and turned to see a pack of red mousses ready to pounce. After overcoming our foes, we saw an astonishing sight: the blossom of whisperweed, a plant that blooms only once in several millenia. Could the monsters have been protecting it?
Strange tubes in the stalk of this plant can carry the faintest noise across long distances. Increasingly rare of late.
The Whisperweed is a piece of loot, obtained by completing the mission "It's the Thought", and is required in order to create the Druid Mace. It is also mentioned in the quest from "Cross the Sea" as a tool for long distance communication between two friends who recently find themselves separated by an ocean.
Whisperweed makes an appearance as a plant that allows communication over long distances. Alba and Dusk use Whisperweed to communicate while being separated in different worlds. Whisperweed is also used when the Warriors of Light are on the Heliogabalus so Dr. Lugae can give them the password to the electronic doors.
Used to reach people far away, it causes one's voice to dim when eaten.
Whisperweed is a trade accessory that grants +4 Luck when equipped, and can only be found in two parts of the Confessions of the Creator.