You are looking at a material called spookyforest

Put this material on something within a forest location to give it an occasional environmental sound. It should trigger once every 20 ticks or so if a player is present.

Some examples of random messages:

From to the south, a falling branch disturbs the quiet under the canopy.

From somewhere hidden, a howl spooks the silence of the trees.

From just out of sight, the cry of a young animal breaks the peace of the forest.
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