The Coelboidae are the most ancient snakes. As the songs of creation burst forth from the heavens, the dragons began to rumble to wakefulness in the bowels of the earth. But those deep places also held other serpents, lesser serpents. As the waning of the time of myth, the lesser serpents faded into the snakes, and their eldest were the Coelboidae. They do not bear claws and wings like the wyrms, they are fully legless, but still at least as long as an elf is tall, and most of the are far larger. They are usually coloured to look like the place they live, and shed their skins often to blend into the area.
The Coelboidae, like their great cousins, exist as partially in the spirit world, often acting as guides or advisors on all things spiritual. They have been known to trade for knowledge and information about the spirits, typically for food, but many of them like gems and other wealth due to fading instincts from their ancient past. They also value their safety, and have been known to hire guards or craftsman to create defenses around them, though their bodies make it hard for them to build their own homes. This is not to say they aren't dangerous, many have sought a Coelboid only to be consumed by the serpent due to an unknown sleight.
The Coelboidae live almost exclusively in the thin places between worlds, and have the ability to slip in and out of this world and the next due to their status as straddling the two worlds. They serve no masters, but they have an incredible sense of justice, and constantly work toward justice, advocating for the Nameless Spirits, the Restless Dead, and the peoples of this world equally, making them often fickle or badly understood by all of those.
Coelboidae eat creatures generally the size of a goat or sheep, but some have been known to swallow a cow or human when necessary. A Coelboid doesn't consider consuming a sapient being to be an act of violence, since it is how they usher a spirit into the next world. Many of them will consume anyone who they think the story of is over, to protect their soul from the ravages of the world. No Coelboid will consume a person they do not respect, since they do not want to be the vessel that ushers their soul beyond. But this consumption has a darker angle. When a Coelboid consumes something, they can then wear their skin. The Coelboid consumes the creature, and after digesting it, it can shed its skin and emerging from the skin is the being consumed. The creature has the mind and soul of the Coelboid, and the Coelboidae often use this for infiltration or diplomacy, though when their nature is discovered, the Coelboid generally is confused at the horror that they receive.
Bound to Wind Embodied In Caves Master of Goat
On The Brink: The Coelboidae are not fully of this world or the next. When they pass through any doorway, whether the entrance to a cave or explicitly the door to a building, they can emerge in this world or the next. While they are in the next world, they are only able to be seen via Second Sight or similar powers, and can only see this world with Second Sight. They are also considered to have Spirit Nature since they cannot interact with this world, but can interact with things with Spirit Nature. This power allows the Coelboidae to speak to and befriend spirits as easily as they do mortals.
Slow Digestion: The Coelboidae takes around a week to fully digest a meal. During this time they cannot engage in any strenuous activity, if they do they have a chance of vomiting forth their meal, which leaves them starving, and unable to eat for several days. This may cause them great distress from hunger as well. Coelboidae generally only need to eat once a month, but if they are already hungry being forced to go days without eating can harm them more, and is a great opportunity for Forte tests for the poor starving snake.
Snake Tongue: The Coelboidae can smell with its tongue, allowing it to taste the air and sense nearby creatures and emotions. It can use its Aura Reading skill to determine emotion, even without using its Second Sight. This trait also acts as a call-on for Perception or Observation when used against Stealthy.
Skin Shedder: The Coelboidae always sheds its skin under the light of the full moon. At the beginning of the first night of the full moon it will begin to slough off its old skin, and by morning it will have fully emerged from the mass of scales, flesh, or fur. When it begins shedding its skin it may choose to emerge in the form of any being it has ever eaten, instead of its own, but only if it is current in its snake form, meaning that it can remain in a form for a moon at a time, and then it returns to its snake form. It can assume a form more than once.
Immortal: The Coelboidae are immortal, meaning they do not die of natural causes and continue to grow, very slowly, past adulthood.
A Burning Wheel Monster Every Week