Are you sure this is a singleplayer world?
stalking.jar is an atmospheric Minecraft horror mod built around the feeling of an unknown presence. It does not rely on constant jumpscares. Instead, it watches, waits, and slowly makes you question what is happening around you.
A silhouette between the trees. Footsteps outside your shelter. Messages that could not have been sent by another player. Small changes noticed just a little too late.
The longer you play, the harder it becomes to tell where coincidence ends and the stalking begins.
The mod intentionally provides no explanation for what is happening. For the best experience, install it without researching its contents and begin a new survival world.
Headphones, low render distance, and nighttime play are strongly recommended.
You are playing alone. At least, you should be.