Found in the most treacherous regions of the Warhammer world, from the Bloodspine Mountains of the unknown Southlands to the Grey Peaks that shoulder the Empire, Basilisks are a reclusive menace. They are a living blight so inimical to life that they poison the very ground they walk upon, the venom that suffuses their body and spirit capable of swiftly reducing verdant land to ruined waste.
Their huge bodies are covered with brightly coloured scales from the membranous fins upon their head to the tip of their muscled tail; a warning of their noxious nature. They prowl stealthily on eight legs, and are capable of moving swiftly enough to run down even the quickest prey. The most potent weapon in the Basilisk’s arsenal, however, is its gaze. Renowned in folklore across the Old World for its lethal potency, the sickly pale eyes of the Basilisk can focus the essence of their poisonous soul, withering their prey until its skin and flesh slough away.
http://www.forgeworld.co.uk/New_Stuff/BASILISK.html
