spirits of mountains and streams
魍 centers on a type of spirit or supernatural being associated with natural features like mountains and streams. It is a specific mythical creature rather than a broad concept.
魍 combines 鬼 (ghost, demon) with 罔, which likely contributes a phonetic element. The character is used for a specific kind of mountain or water spirit in Chinese and Japanese folklore.
The ghost radical 鬼 wraps around 罔, which looks like a net over a mountain. Imagine a ghostly spirit trapped in a net over a mountain stream: that's the mountain and stream spirit 魍.
For モウ, picture a mountain spirit mowing down trees with a ghostly scythe: mow -> モウ, and the spirit haunts the mountain.
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