There are several episodes where they encounter ghosts or spooky situations, like:
* "Scaredy Pants": SpongeBob is terrified of a ghost in his house, but it turns out to be just a stuffed animal.
* "Ghost Host": SpongeBob becomes a "ghost host" on a haunted house ride, but this is more of a roleplaying scenario.
* "Ghost of a Chance": SpongeBob and Patrick see a ghost in a haunted house, but it turns out to be the ghost of a jellyfish they accidentally killed.
Let me know if you'd like to know more about these episodes!