The Forel are clusters of trees which, through an infestation of semi-intelligent fungus similar to the Sporen, have a sort of hive mind which allows them to react to intruders in their midst.
Individual Forel are unintelligent and unable to take action against enemies. But when there is a critical mass of them in one area, they gain enough cohesion to be able to act. The Forel are able to psychokinetically move their forms to attack creatures unfortunate enough to stumble into their midst. Oddly, they do not attack for any discernable reason; it is not for nourishment, and not for defense. They just seem to strike at whatever comes in their midst, regardless of whether they are a threat to them or not.
The canopy of leaves around the Forel typically hides a carpet of shattered bones of various woodland creatures. The Forel attack by swinging their massive branches at their prey, and using thick, twining vines to restrict movement, hamper actions, and draw its targets within range of the branches.
There is no good way to fight back against the Forel; the best strategy is to escape. Failing that, destroying the attacking limbs will render the Forel impotent but still alive. Only purging the site with fire, or otherwise somehow destroying the fungus that burrows through their wood, can permanently destroy a grove of Forel. (However, it may be a boon to one who does this, for the carpet of bones may hold the remains of long-dead adventurers… and their possessions.)