Issie is a lake monster claimed to inhabit Lake Ikeda, on Kyushu Island in Japan. The name Issie was formed as an analogy to “Nessie”, the Loch Ness Monster.

The legend comes from a myth that Issie was a white mare and had a foal. They lived on the shores of Lake Ikeda. When her foal was kidnapped by a samurai, she searched desperately to find it. In despair she jumped into the lake and was transformed into the lake monster. When she surfaces, the legend says she is searching for her lost foal.

Five photographs have been reportedly taken in 1978 by a man named Mr. Toshiaki Matsubara. However, only a few people have seen them and they have not been released for analysis. Twenty other people also claimed to have seen the creature the same year.

It was described as being around sixteen-and-a-half feet long and black. Another sighting in 1991 was claimed, and supposedly a video recording was taken. In this account of the creature, it was described as being almost 100 feet long.

Issie was used in the movie Godzilla, Mothra and King Ghidorah: Giant Monsters All-Out Attack. In the movie, Issie is the Larva of Mothra and cocoons into an adult.

There is a statue erected of Issie and an observation platform by Lake Ikeda where the sightings occurred, so visitors may actually catch a glimpse of this fabled legend.