Baldur's Gate 3 - how to open the sinister door in Cazador's Palace

How do you open the Baldur's Gate 3 sinister door? You may have visited Cazador's Palace on purpose - with a purpose - or you may have just stumbled across the weirdly insular, super fancy part of Baldur's Gate. Either way, there are all manner of strange folk inside, and a really big, magically locked door. A sinister door, if you will.
If you've read our Baldur's Gate 3 review you'll know there are innumerable wonders to discover across its many areas, but not many can top the strange factor that Baldur's Gate 3's Cazadors Palace offers. Brainwashed minions, a dead werewolf, and... vampires? If you want to know what's really going on, you'll have to find your way past the sinister door and into the mysterious dinner party. Maybe just prep your BG3 class in advance in case a fight breaks out.
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