Why Pennywise WORKS while The Mind Flayer Doesn't

So, I just finished IT: Welcome to Derry and I really enjoyed it. But while I was watching it, I could not stop drawing parellells between Pennywise, and Vecna, and by extension The Deadlights and The Mind Flayer. They are both cosmic entities in their original form, and they both have vessels in their physical form. But even with those similarities, I can't help but feel that Pennywise is significantly more scarier than Vecna. And in this video essay, we are gonna compare these villains from both Stranger Things and the IT franchise. The nature of both Pennywise and Vecna, and their cosmic counterparts, The Deadlights and The Mind Flayer. We are gonna check out the similarities and also the crucial elements that makes one better than the other. And we are gonna finally come to answer on why Pennywise is scarier than The Mind Flayer, and why Pennywise WORKS while The Mind Flayer Doesn't.