The natives of this planet have four arms. They live a primitive life, comparable to a stone age that has not yet mastered forging bronze. At least one tribe has developed both domesticated mounts and the fashioning of copper weapons, and is fast becoming a major regional power.
Much of the world is still untamed wilderness, unchanged by agriculture or settlement. In addition to fungal forests of wide-surfaced flora, some leafless plants covered in a photosynthetic exterior grow into massive structures, whose cavernous interiors are often home to nomadic sapient hunters as well as lairs for beasts.
Due to the prevalence of vertical structures such as massive trees and cliff gorges, the ability to climb and fly is commonplace among the fauna. Curiously, an omnivorous diet is nearly universal among most large species; anything larger than an Earth mouse survives by the flexibility of being able to eat a wide variety of foods.
Reflecting the shapes of the flora, what limited buildings the sapient life do build have the same bulbous and curved forms. These buildings appear to be primarily made as look-out towers, landmarks used as part of long-term communication; people leave messages there for others to find, and from the tops other such towers can be seen, aiding navigation.
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