Great Iridescent Forest

The iridescent forest follows the stationary twilight line for most of its length, taking most of its original light and nutrition from the edge of the forest, much farther upstream of the Still River, where Light's radiance can touch it partially across a whole dimming cycle. It covers the bigger part of the land between Montelume and Lorelume, with a small gap midway where the (you need to complete this clause).

The Lumin energy is rich in this forest, and every lifeform holds a considerable amount of it. Most of these lifeforms have developed a sixth sense for Lumin energy and can see and feel other lifeforms through this Lumin-sense. Other species of trees, plants, predators, and prey have instead developed particular defenses and forms of camouflage based on their affinity to Lumin energy. This makes the forest a particularly dangerous area for domers (people originating from domes), due to the wild Lumin energy there being completely different and alien from the one nurtured inside domes.

Flora

The All-Tree

Early scholars, accompanied and guarded by Traders, first thought that all trees were their own species. Eventually, it was discovered that, through careful analysis of their Lumin signatures, all trees shared the same rhizome of roots and were actually the same organism expanding as a whole over a vast portion of the known Twilight Lands. Some Lumin experts, well-versed in this particular ecology, even hypothesized that a massive central organism—a gargantuan tree potentially rising hundreds of meters—could exist much farther in the light of the Sacred Lakes, since it seemed, according to Traders, that the more you followed the forest with Light on your left, the denser the rhizomatic networks became. To support this hypothesis, there is also the fact that the waves of light coursing through the trees seem to originate from a particular direction.

Nonetheless, the forest's trees appear to communicate between themselves, exchanging nutrients through their roots depending on the needs of each individual. The foliage, composed of coniferous and deciduous trees, is extremely dense so as to capture the maximum light possible. The trees also seem able to reemit part of the light they receive through the roots as radiance escaping through cracks in their bark. These cracks are filled with a dense, solidified, transparent resin that the tree produces to protect the damaged bark. When a Lumin pulse travels, the trees breathe light—soft fractures of gold shimmering through resin veins, like distant lightning trapped beneath bark. In turn, other trees can receive this generated light through their foliage, mostly in the lower parts of the canopy.

None of this would be possible without the immense and continual intensity of light coming from the Sacred Lands, forever bathing this forest in a small portion of Light’s radiance.

Moodswinger

Moodswingers are somewhat rarer trees that manage to find space within the dense root network of the All-Tree. Their bark is not hard; instead, it is covered in countless tiny fibers that give it a smooth, velvety texture. Their leaves begin the year a bright gold and fade to a deep blue as the dimming cycle progresses.

Their fruits, about the size of a fist, drip continuously with savory, enticing juices meant to attract animals. Fortunately, Moodswingers do not reproduce aggressively, for they are extremely insidious plants. They manipulate the Lumin inside nearby lifeforms—mostly mammals—to alter the target’s emotional state.

At the beginning of the light cycle, when the fruits ripen, the tree emits waves of bliss and euphoria. Animals gather excitedly to eat the fruit and, in doing so, spread its seeds. This phase lasts three to four moons. Afterward, the emotions it projects shift gradually into lethargy and despair (Traders have even reported experiencing sharp episodes of depression when passing nearby).

Creatures eventually fall asleep beneath the tree—and never wake again. Their bodies decompose at their base, enriching the soil for the next cycle. After four to five moons of this dormancy-feeding phase, the tree begins forming new fruit, just in time for the next dimming cycle.

Fauna

Beterast

Beterasts are migrating herds of herbivores that frequent the forest during the high light. Peaceful but easily startled, they are broad-shouldered, long-legged grazers with a thick hide ideal for enduring predator attacks. Their most striking feature is the pair of long, intertwined antlers that rise from their skulls. These antlers glow with a dim, textured blue light and serve as a medium for expressing emotional states such as fear, joy, or anger.

Within a herd, they use these pulses to signal danger and coordinate movement, allowing the group to shift direction as a single organism. Traders have reported seeing an entire herd avoid a massive pack of Pale Stalkers by sending rapid waves of green signals through individual members. Because of this luminous behavior, a herd of Beterasts is called an aurora.

They primarily feed on the lower leaves of the All-Tree, pruning the understory efficiently and allowing more inner light to rise toward the higher canopy layers.

Prismatic Hunter

The Prismatic Hunter is widely regarded as the apex predator of the Iridescent Forest. This massive feline carries a thick pelt in which every hair strand is infused with Lumin energy, enabling it to camouflage flawlessly anywhere in the forest. It prowls mostly in the darker regions, syncing the coloration of its coat to the shifting glow of the trees with near-perfect precision.

Its jaw houses three rows of serrated teeth, including two pairs of oversized incisors on both the upper and lower jaws. When it bites, the mechanism of its skull allows it to clamp down with locking force, making escape virtually impossible once contact is made. Its teeth can tear through flesh and grind most bones, leaving almost nothing behind after a kill.

Unfortunately, the only reliable way to detect a Prismatic Hunter is not through sight but through refined Lumin-sense. Just before it strikes, there is a brief moment when all surrounding Lumin activity falters—an eerie stillness in the air—signaling that the hunter is about to pounce.