From a distance a Root-Host is a person wearing a fine grey-white fur. Close up the fur is mycelium, threads finer than hair matted over the skin and clothes, thicker at the joints and the mouth, where it hangs in soft beards. At night it glows a cold, pale blue, so that a crowd of hosts in a wood is a drift of blue lights among the trees. Here and there a thread runs from one host to the next, or down into the ground, and those threads pulse slowly.

They move in step with each other, breathing together, turning together, raising their arms together like dancers at one tune. They are silent but for breath and a faint creak, like roots stirring underground. They smell of leaf mould and mushrooms and damp earth after rain, a smell many people find comforting.

They would live in an Incursion of Xylos, where living growth carpets the ground and limbs and faces of the taken are grown into the mass, and in forests, fields, and cellars where its threads had spread. Because the Network travels by root and fungus, Root-Hosts could rise from ground far from any visible Incursion, in a wood where people go to sleep.

They do not attack. A Root-Host comes close, opens its arms, and presses near, gently, the way a friend embraces, and where its mycelium touches bare skin it roots. Many hosts together close slowly around anyone still separate, patient and untiring, until there is no gap between them. What one feels, all feel: a wound in one host bleeds in all, and a meal eaten by one feeds all.

There is a kind of tenderness in them, without any person behind it. They do not hate the separate; they want them home.

A Root-Host’s touch is a graft. Threads spring from its skin into the next skin, join nerve to nerve, and within hours the rooted begin to share thoughts and sensations with the Network. Hosts sense each other and their prey through every thread that touches the ground, so one cannot easily hide from them in soil or wood. Inside the Graft, magic, life, and thought that depend on a separate self all fail (see what every Incursion shares).

They are held off by separation. A closed body, covered and whole, is hard to root; a will that pulls the other way resists the graft; a thread torn out at once does not take. Fire burns the roots back.

Root-Hosts are made, and a Cult of the Great Root, whose members would open their bodies to the Network, would most often be rooted in at the end. A host lives as long as the Network feeds it. In time it walks less and grows more, until it settles into the mass and becomes part of the growth itself, its face still warm among the roots.

To the lonely, the Root-Hosts offer what they long for: perfect closeness, and an end to being apart. That is the whole danger. Survival means refusing comfort, even from friends, and travellers near an Incursion would sleep off the ground, keep their skins covered, and not hold hands.

Root-Hosts would easily be taken for the gentle folk of a forest tale who take a lost child home. Whether any self would remain inside the blue glow is not known. Fungus fires and blue rot in timber are sometimes taken for omens of the dark; usually they are only rot.