Resident Anna describes several examples:
Early games in the series also echoed Wright’s distaste for typical American consumerism, and this was evident in the feature known as the “build and buy catalogue.” Both in the snarky names and descriptions of items, but also the ways that the purchase of certain assets could have real impact on the gameplay (google “Sims guinea pig disease” if you want to learn more). The most famous (and creepy) instance of this, comes in the form of The Tragic Clown.
First introduced in The Sims: Livin’ Large expansion pack, Sunny the Tragic Clown is one heck of a nuisance. As a prerequisite for the following events to unfold, your Sims must have the “Tragic Clown” painting hanging somewhere on their lot.
If a Sim’s needs drop too low and they become “depressed,” an NPC named “Tragic Clown” will visit your lot in an attempt to cheer them up. Unfortunately, he’s really bad at his job, and mostly hysterically sobs, bothers your Sims, and makes everyone in general feel even worse. His eerie presence is oddly “sticky,” as he’s really hard to get rid of once he’s arrived on your lot.
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In researching for this article, I cannot tell you how many comments I’ve seen on Reddit or YouTube about how they frightened someone as a child