Franchise context: The write-up below is from the parent franchise article (anime, book series, or IP) rather than the card game itself. A dedicated CCG profile has not been written yet.
Natural Monuments (Korean: 천연기념물) is a national-level designation within the heritage preservation system of South Korea for animals, plants, landforms, geological formations, and nature reserves. It is administered by the Cultural Heritage Administration according to the Natural Heritage Protection Law (문화재보호법).
Source: en.wikipedia.org/wiki/Natural_Monuments_(South_Korea)
