Lake worms, also known as sea worms or water-worms, were giant worm creatures living on the rainswept Outer Rim Territories planet Daluuj. By 0 ABY, two of these creatures dwelled at the bottom of a mud lake and made trouble for the Heroes of Yavin when they dragged the Millennium Falcon down to the lake's watery depths. They were impervious to blaster fire, as Ackbar and his crew found out the hard way. Exactly what they did to the ships after submerging them are unknown, although Ackbar stated that they do not eat them. Ackbar later speculated that the worms attacked various ships because the sounds of engines irritated them, whether it be skimmer engines or starship engines.