Sandworms are enemies from Phantom Hourglass.
Boing-oing! Creatures that are sensitive to sound dwell in the sands ahead. So, walk without sound and bring as little attention to yourself as possible. If all else fails, flee to a high spot before the creatures find you.
Sandworms dwell in sandy areas of Isle of Gust and Temple of Wind. They are creatures that are triggered by sound, moving quickly towards the source. Walking very slowly will keep them at bay, but if Link runs, they will come charging from underground towards him. If caught, rub the stylus on the screen quickly to shake free. Their one weakness are Bombs. Just toss one near them and it will gobble it up and soon explode. If Sandworms come charging towards Link, he can escape by running away from sandy areas or toss a bomb to distract them.