These are magical beasts, summoned by worshipers of Lilith as guardians and trackers. They are utterly silent, even when moving through areas where they should make noise. They do not bark, or make any other social canine sounds. The only vocalization they have is their howl. That howl is a sound of terror and death, sounding different to each person that hears it. The beast radiates an aura of fear that only those bonded with them are immune to.
They look like long legged hunting hounds, being slender of frame, with narrow heads. Their muzzles are full of short, very sharp teeth, which they use to shread their prey. Thier primary diet is not flesh, however. It is fear. They feed by some unknown manner on the fear they create, which is drained from their victims like life force. They also drain the life energy from the earth around them, and can nullify incantations created with that magic by draining it. It is not known how they affect other forms of magic.
One tribe of Lutins has taken these creatures as their tribal totem, having any number of them with their tribe at any one time. The entire tribe seems to be immune to their fear effects.
Moondogs cannot exist alone once they separate from their mothers (at approximately 6 months of age), so no 'feral' or wild Moondogs will be encountered. During the period of separation from their mother they are forced to seek out and bond with a sentient being (typically Lutins specially chosen by the Moondog Clan). While it is assumed that they only bond with Lutins they, in truth, can bond with any sentient in the right place at the right time to form the required spiritual bond. A pup that does not bond sickens and eventually perishes within two months as they cannot spirit bond to other Moon Dogs.
Once bonded a Moondog takes on the intelligence of their spirit partner, and extend to that partner the long lifespan of the dog (70-100 years) and the senses available to both parties. Thus when paired with a highly educated individual Moon Dogs can learn to read and manipulate objects with their paws but not speak (they lack vocal organs).
Death of the Moon Dog (an extremely difficult task to accomplish - they are extremly resilent beings with commendable regeneration) means death of their spirit bonded partner. Death of the partner likewise becomes the death of the Moon Dog. They leave no corpse, fading into white mist within moments of death.
Bonding & Faith of Lilith
As stated, Moondogs can bond with any sentient being they encounter. They loose much of their link to Lilith if that being is not a follower of her faith and become unbound spiritual beings that form a symbiotic relationship with the sentient that has bonded to it. Their fear power becomes dramatically less or even nonexistant while their bodies and teeth change to a more wolfish form capable of consuming meat normally. Their biology changes to a more mortal existence but they are still beings of spirit merely released from the Hells that Lilith discovered them in.
Once free of Lilith they begin to take on the morality of their spirit partner (truth of the matter is that they always did) which may not be seen as any big change due to the fact that they were only linked to Lutins selected by the Moon Dog Clan. They confer a considerable extension of life to their bondmate as well, enabling the usually short lived Lutins who are their chief bonding race to live as long as they.
Bondmates also gain the Moondog's resistance to injury, sickness, and disease but lack the ability to regenerate though their healing is more swift. The saliva of Moondogs is also very antiseptic; wounds caused by bites do not fester but will scar more noticeably than usual. Lutins use this trait to create scar patterns on themselves.