The fierce snake or inland taipan can reach a total length of 2.5 metres, although 1.8 metres is the more usual length. The upper surface of the snake can vary from dark brown to a light straw colour. Dramatic seasonal colour changes take place, with a darker winter and lighter summer coloration. These changes are an adaptation to the harsh outback climate, the darker markings absorbing heat more efficiently in winter and the reverse in summer. The head especially may take on an almost glossy black appearance at times.
The fierce snake inhabits the black soil plains in the region where Queensland, South Australia and the Northern Territory borders converge. There is little in the way of cover or vegetation, the snakes utilising the deep cracks and fissures formed in the dry soil to escape predators and the searing heat.
The diet is almost solely composed of small mammals, particularly native rats, which, at times, reach plague proportions in this region. The prey is subdued with a series of rapid accurate strikes, which injects the extremely toxic venom deep into the rodent. The venom is unequaled in toxicity amongst any snake anywhere in the world.
Populations of this snake are highly dependent on the availability of its favourite prey. When the rats experience a good year, the numbers of fierce snakes also rises soon after. By the same token, when a poor year follows many rats and snakes perish from lack of food. The female fierce snake lays between 12 and 20 eggs per clutch, which are laid in an abandoned animals burrow or deep soil crevice.