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Introduction[]

Gillyweed is a magical plant, usually found in the Mediterranean, which allows the consumer to breathe underwater. The plant is a greyish green colour, and resembles slimy rat tails.

From the Story[]

Harry Potter and the Goblet of Fire[]

Discovered in chapter 26, The Second Task[]

Dobby brings Harry a ball of Gillyweed on the morning of the second task. Once eaten the effect of Gillyweed happens quite suddenly; Harry feels as though an invisible pillow is clapped over his mouth and nose, and his lungs feel as though they are empty. He feels a piercing pain on either side of his neck, and gills appear just below his ears, preventing him from breathing as usual but allowing him to breath under water. As well as growing gills, Harry's hands and feet become webbed, his feet elongating to resemble flippers.