Having a haunting can be predictably chaotic, given the damage they could cause overnight, but they're mostly a minor nuisance that sometimes leads to funny moments and overall has a negligible impact on gameplay. Ghosts tend to behave erratically, but also in ways tied to the type of death they experienced. The presence of their urn (indoors) or tombstone (outdoors) is what determines the lot they will spawn on. Ghosts will visit in the middle of the night (after 10) and depart in the morning (around 6am).
While there is some variation in what ghosts can do and how they behave, they also share the same qualities. This guide to Ghosts will teach you about their attributes, means of getting rid of ghosts, having ghosts join your household, and how to bring a ghost back from the dead. We have a separate guide to individual ways Sims can die, and preventing death. They are the result of Sims who've passed away, and their behavior and abilities vary based upon the cause of death. Ghosts are a feature of the Sims 4 Base Game. The Sims 4: Ghosts Removal, Resurrection, and Joining the Family A Ghost