Warning: SPOILERS for Stranger Things season 4.
There are a handful of meanings behind the grandfather clock appearing to Vecna's victims in Stranger Things season 4. One of the first elements from Stranger Things season 4 to be teased to fans was the grandfather clock (way back in 2020), though no one could understand what the marketing team was trying to get at with its inclusion in various teasers. Unfortunately for the people in Hawkins, as it turns out, it's a sort of calling card for Vecna, the new villain in season 4.
Vecna isn't a monster like the Demogorgon or Mind Flayer and he isn't after Eleven or her powers; rather, Vecna is a humanoid, dark wizard who is using his powers to amass some sort of team, similar to what the Mind Flayer did in Stranger Things season 2 with the Demodogs. But there's more to it; he isn't choosing people at random, nor is he killing them whenever he wants to. He's quite calculated in his modus operandi, first going after people psychologically and then with visions, before finally bringing them into his realm.
Related: Why Stranger Things Season 4 Took So Long To Happen
As Max explains, Vecna first goes after his victims by causing intense headaches, then nosebleeds, and ultimately, visions of their past trauma. For Max, that's seeing Billy, who died during the Battle of Starcourt. But before Vecna comes for his victims, he provides them with a vision of a grandfather clock, essentially letting them know they have less than a day left to live. Max put together the timeline and noted that Chrissy and Fred (and later Patrick) all died within 24 hours of having their first vision. Furthermore, this falls in line with Henry Creel's obsession with world order and emphasizing that time —
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