The basilisk is an eight-legged reptile with a nasty disposition and the ability to turn creatures to stone with its gaze. Folklore holds that, much like for the cockatrice, the first basilisks hatched from leathery eggs laid by snakes and incubated by roosters, but little in the basilisk’s physiology lends any credence to this claim.
A basilisk prefers to eat petrified flesh. Once a victim has been turned to stone, the basilisk crunches the fossilized corpse with its powerful jaws and lets its potent stomach acids do the rest. This digestive process is extremely slow and inefficient, causing the basilisk to move so lethargically that it appears as if in mid-petrification itself. This has even led to the saying “as slow as a wellfed basilisk.” Certainly basilisks are well-known for their slow gait and slothful nature, but a predator that can turn its prey to stone with a glance hardly has much need for speed.
An adult basilisk is 13 feet long from head to tail and weighs roughly 300 pounds. These reptiles make hissing sounds when moving about that turns to a guttural gurgle when they’re agitated. Though they are normally solitary creatures that come together only to mate and lay eggs, there are periodic reports of regions being infested with unusual numbers of basilisks. What causes these unusual congregations of basilisk activity is unknown.
For unknown reasons, weasels and ferrets are immune to the basilisk’s stare, and they sometimes sneak into basilisk lairs while a parent is hunting in order to consume eggs or freshly hatched young. Some legends suggest that a basilisk’s blood can transmute common stones into other material, but this is likely a case of witnesses misinterpreting the magical restoration of previously petrified creatures or body parts.