The Silver-Toothed Tunneller, is a a rodent with some unique qualities. Silvrum-infused, they find themselves gifted with jaws and digestive systems that are able to consume most known materials. This, when combined with their claws, make them efficient tunnellers that are able to dig through any material, allowing them to invade even the most hardened fortresses.

They are slim in nature, more similar to eastern dragons in terms of general appearance. Long thin bodies, with long necks and tails that have a flexibility quite like snakes. Their faces feature long snouts, filled with sharp silver teeth that can bite through most materials. Their claws are of a similar colouring, and are short and curved, hook-like to aid in climbing and digging. Four toes to a paw and a thumb, the creatures are quite able to manipulate items small enough for their paws, and in some case, larger. Whilst they don't often utilise tools, they have shown an affinity for mechanical 'toys'.

Their rodent nature comes from their ability to invade, their ability to reproduce, and the difficulty in removing them from a location, making them the comparable to rats in nature.

Whilst they are normally scavengers, and will avoid detection and confrontation where possible, they are still hunters, more then happy to chase and consume creatures smaller then them, or creatures weakened by illness or injury. Their aversion to pack behaviour, is a blessing however, as numbers of them could easily overwhelm creatures far larger then they are.

In terms of size, young Tunnellers are often no larger then small cats, whilst adults are rarely larger then a smallish dog, rarely being larger then half a meter in terms of body size. However, under the right conditions, they can easily grow to be a meter in size, allowing them to become dangerous predators.

They do display intelligence, able to evade detection and traps quite easily, although they have an affinity for shiny items, making them akin to magpies. This is an issue for locations such as banks, who will regularly have to check for infestations to protect goods. It is not unheard of for them to steal firearms, or other items that catch their attention.

In terms of breeding capabilities, they display unusual behaviour. Whilst they can breed with their own kind, they prefer to avoid them, instead breeding with other species. Omnifertile and virile, males will often mount fertile females of other species in their sleep, whilst females will invoke an arousal within males of other species before taking advantage during sleep. Armed with potent pheromones, it’s not unheard of them subduing targets to then take advantage of.

A single female can put out anywhere from a dozen eggs, to several dozen in a single fertility cycle, where as eggs developing in other species will secrete chemicals into the ‘surrogate’s’ body, manipulating their behaviour to protect the growing young, before laying them in optimal locations. Often females who have become surrogates, will become affectionate to the males of the species, and even ignore nests.

Females of the species, are know to have extremely accommodating internals to allow for a range of species and sizes, whilst males will extend a prehensile shaft from their slit, that will swell to fill a female to capacity. The most identifying aspect of the male anatomy is that they have a tapered tip, and will attempt to work their way into wombs of creatures, but both are able to recognise a range of species, and replicate reproductive anatomy to enhance sexual compatibility, as well as invoke reproductive instincts.

Countermeasures against the creatures are often unpredictable at best. Whilst the most consistent method is through sonar repulsion, the most effective way is through chemical marking.

Sonar repulsion works via installing devices that give off an audio frequency that the creatures are sensitive to. The general idea is to make an environment unpleasant, so they don't nest, and simply avoid the area.

Chemical marking works a little differently. Since the creatures avoid their own kind, marking areas with urine will often trick them into thinking there are competitors nearby. Whilst it may not drive them off immediately, overtime it will often serve as a powerful deterrent.