The Acorn Pokémon closely resembles an acorn, complete with two beige “feet.” It sports a gray cap that partially covers its head, adorned with a beige, mask‑like pattern across its face. Its eyes are large and dark, featuring beige pupils.

The Acorn Pokémon clings tightly to tree branches, suspending itself there as it absorbs moisture and nutrients to sustain life. When it remains perfectly still, it’s virtually indistinguishable from ordinary tree fruits. On young, towering trees, rows of Acorn Pokémon can be found hanging in clusters. To expand its range, it cleverly disguises itself as a fruit, luring Bird Pokémon to carry it far away. The more water it drinks, the smoother and shinier its body becomes—and once its meal is finished and its body grows heavier, individual Acorn Pokémon gradually fall to the ground. Occasionally, strong winds will dislodge them as well. Each day, it uses its leaves to polish its body once, keeping it gleaming and pristine. It delights in startling other Pokémon by suddenly darting into motion, taking great pleasure in scaring off Popo or other Pokémon that might try to peck at it.