Corpora are nasty, greedy things that carve out their survival off the efforts of other creatures. Similar in form to a hairless, lean ape, a corpora's strength and intelligence are not apparent until after they've developed a nest from which to operate. Corpora are highly competitive with other creatures and individuals of their own species, due to their high demand and need for resources. Settlements that encounter a corpora are encouraged to rid themselves of the pest quickly or hedge its efforts in such a way that it can never settle.
They start small, both in strategy and lifecycle, as Picking Corpora that scout out settlements or small herding grounds where other creatures frequent. During this stage, picking corpora identify where the valuable resources are by observing the local community or wildlife go throughout their days. This often involves figuring out where the coolest streams run and the richest vegetation grows. Once a Picking Corpora has figured these things out, they quickly set to work building their nest near these resources.
Once their nest is complete, a corpora will mature into its more aggressive stage known as the Settled Corpora. A settled corpora's strategy now involves bullying the local residents around their nest until the resources are highly guarded and difficult to access without crossing the corpora. But, a settled corpora does permit some creatures to -- for example -- drink from the stream or eat of its berries so that it may illicit trade. What this means is the more intelligent creature's will eventually learn to offer -- another example -- berries from far away to access the water. This strategy often leaves less intelligent creatures with no alternative but to migrate far away for different grounds.
There are not many records of such a creature yet, but oral tradition speaks of corpora left to settle for decades -- often called a Crowned Corpora. It is thought that such corpora can grow in strength and size to such a degree that the creature becomes one with its nest. When this happens, a crowned corpora can siphon resources -- both magical and mundane -- straight to itself like a valley in which water pools.