As mentioned above, velikans contort their bodies with diseases. Every disease reshapes their bodies in different ways, usually adding rotting flesh, vegetation, or extra limbs. They cannot die from disease. It will only make them more fearsome. They have supernatural size, strength, and agility, and their blood contains ichor, which makes their blood very powerful. They have the innate ability to understand what their peculiar farming focuses need.

Velikans can sense poisons, toxins, pollutants, bacteria, fungi, and viruses, as well as other sources of disease and illness, innately. They know when their environment is attuned to creating such things, and if many velikans gather in a vibrant place for more than a season, it will begin to rot.

Velikans can gain strength by cannibalizing each other and often do if needed.

Velikans live in contentious farming communities, focused on individuals who control large ranches within the vile swamps. Each ranch is controlled by the most vicious, powerful velikan, who usually controls what diseases are the focus of the ranch. They are usually a powerful elder, and they control the rest of the velikans through a feudal arrangement, being a lord among serfs. Lords usually bribe powerful velikans to serve them as enforcers, police, military, and advisers.

Newborn velikans are left in the disease beds for a week to see if they survive. They are not nursed, but rather, survive on vile energy produced by whatever they are first infected with. If they live a week and become strong enough to walk, they are put to work. If they cannot walk after a week, they are drowned, left to rot, then eaten. Once a child reaches an age where they can fight for some supremacy amongst the other children, they are taken underwing by an older velikan, who uses them as a personal servant, infects them with various diseases to see what happens, and grooms them to be a lifelong asset. During their final growth spurt, which functions similar to other giantish final growth spurts, they are tested continually with new infections and toxins, distorted beyond recognition. After this, they are an adult. If they never have a final growth spurt, they resort to cannibalism or disease to trigger it, or they are killed, rotted, and eaten.

As adults, velikans usually begin to rebel and attempt to break free of their masters. Most fail and remain in servitude, but some succeed and takeover either a ranch or a whole community.

Velikans have their own special celebrations for themselves. Lords celebrate milestones in their own lives and anniversaries of great events by feasting in front of their servants and bringing in new infections. Major celebrations include their birthday, the anniversary of their taking control of the ranch/community, the anniversary of contracting their favorite disease, and the anniversary of their reaching adulthood. When they die, a conflict ensues for control of the ranch/community. Rivals usually kill, rot, and eat each other.

Velikan lords do not court, but coerce their serfs into coupling. Children of lords are rarely kept or honored except in the later life of the lord, if they want to try to groom their successor. Courtship among serfs is different, focused on matching diseases, and usually involves trading food and courting in secret. It is largely based on physical attraction and useful alliances.

The homes of velikans are usually made of a collection of hollowed out giant toadstools. Each toadstool is a different room or small set of rooms, usually including bedrooms, kitchens, outhouses, dining areas, crafts rooms, disease beds, storage space, punishment areas, and a pantry. The stench in velikan communities is enough to drive most non-locals away.

Velikans who escape the feudal system usually live as mercenaries, fell esotericists, or beggars.