The lake dragon was a giant aquatic plesiosaur-like creature that lived in a large lake. When Lina Inverse and the Slayers decided to order Dragon Cuisine in a restaurant, Ashford the Chef led an expedition to capture the creature.
The lake dragon is remarkably huge, much larger than Ashford's ship. Although it does not seem to have any special powers, it is extremely powerful, thwarting all the Slayers' attempts to capture it. He broke through the dragon net, destroyed the boat, and nearly ate Gourry, mistaking him for a large shiny fish.
Finally, Ashford, invoking his secret technique, the Secret Strike Shooting Star Cleaver Slash, slew the mighty beast with a santoku.
Unfortunately for Lina, the lake dragon's meat is extremely poisonous unless it is rightly prepared, which takes several months of cooking. But, according to legend, once cooked properly, it is considered one of the most delicious meats available.
Although the cooking times of the lake dragon may seem ridiculous, there is a real creature - the Greenland shark - that may be the inspiration behind the lake dragon recipes. The Greenland shark is highly toxic to eat, but can be safely consumed if the meat is properly prepared in a process that takes several months to complete. Some of the cooking processes that Ashford describes are very similar to Greenland shark preparations.