The Plain of Fear is a bizarre desert in the eastern portion of the northern continent. Among its many dangers are supernatural, reality-distorting "change storms" which can transform any living thing unfortunate enough to be caught in them. It is inhabited by over 40 unique and intelligent species such as windwhales, flying mantas, reversed centaurs, talking buzzards, and enigmatic talking stones called menhirs. Most important is Father Tree, an alien entity worshiped by all the creatures and the rare wild human tribes as their god.
The Plain was mentioned in passing in The Black Company and described briefly from the air by Croaker in Shadows Linger. Then, the Plain had become the home of the Black Company for two years before the opening events of The White Rose. The hordes of Plain monsters became critical allies to Darling's New White Rose Rebellion.
Before the AnnalsEdit
In the distant past, possibly 1,000 years before the Dominator, a profoundly powerful sorcerer became a monstrous tyrant but was overthrown and buried alive. To keep him within the ground, the victors summoned an "adolescent god" from another world or plane, who appeared in the shape of a sapling. The summoning was so explosive that "thousands perished and counties were devastated", indicating that the Plain had once been populated by humans. The god-tree grew his roots and entrapped the evil tyrant, and the Plain became populated with the bizarre species that leaked over from the tree's world. He became Father Tree, and he and his prisoner became all but forgotten by humanity.
For centuries afterward, Father Tree protected and commanded the Plain creatures, and was worshiped as a deity by "scarce wild human tribesmen" who inhabited the desert.
The Black CompanyEdit
Whisper, after being Taken by the Lady, defeated the armies of her former allies Moth and Sidle in the Plain of Fear. Not long after that, the Taken Nightcrawler led an army through the Plain and approached the suburbs of the Rebel-held Thud.
In the years leading up to Shadows Linger, the Black Company crossed the Plain of Fear alongside larger armies of Imperial regulars, under the aegis of the Taken Whisper and Feather. Despite their powerful backup, the Company still lost at least two men (Cougar and Fleet) to the dangers of the Plain. In the eastern town of Tome, Croaker would recall this memory with immense dread; to his chagrin, they would soon be ordered to return west, back across the Plain. The Company and a caravan were led across the Plain by the Limper, but Croaker was flown over the airspace via Whisper aboard her flying carpet. Despite a harrowing encounter with flying mantas, those on the carpet were unharmed.
The White RoseEdit
The diminished Black Company (now enemies of the Lady) and Darling entered at the Plain four years after the Battle of Juniper to escape the new Taken. With the menhirs' permission, they made their headquarters in a stinking, cramped series of caverns called the Hole, not far from Father Tree. For two years after their arrival, Darling and the Company orchestrated their New White Rose Rebellion against the Lady and her empire.
One of the Plain's infamous change storms overtakes a windwhale which was carrying Croaker, One-Eye, Goblin and several others. Despite these veterans' familiarity with dangerous situations, they are stunned by the terrifying experience.
After Father Tree reveals his sentience, he begets a Sapling son, and gives him to his new servant Tracker to assist Darling and the Lady in their upcoming battle with the Dominator. The Sapling was removed from the Plain, replanted in the Barrowland, and had the silver spike containing the Dominator's dangerous power driven into its trunk. Father Tree and the Sapling maintained a psychic connection despite the vast distance between the Plain and the Barrowland.
The Silver SpikeEdit
A vast army of Plain creatures is granted by Father Tree to Darling during the events of The Silver Spike. They are indispensable in Darling's pursuit of the Limper (at this point known as the "wicker man"). A second, potentially larger force, is sent out from the Plain to rendezvous with the first group outside the city of Oar. There, the combined Plain horde helps defeat the Limper and secure the silver spike for the second, and final, time. The horde returns to the Plain and Darling gives Case a tour of the abandoned Hole.
Croaker mentions the Plain of Fear when observing the Unknown Shadows whilst at the Abode of Ravens. He speculates the inhabitants of the Plain of Fear may have came into being in a similar, but unrelated way much like the shadows on the glittering plain.