I have a slight feeling you’re making it more complicated than it needs to be… Like, how are you in a building with security cameras AND illusions? Surely the illusions make it harder for the cameras to do their job. And surely, since you’re in a building, the giant worms can’t get close enough to affect anything. Plus, the number of banshees would be unchanged since 10 feet ago, as would the scry spell.
I have a slight feeling you’re making it more complicated than it needs to be… Like, how are you in a building with security cameras AND illusions? Surely the illusions make it harder for the cameras to do their job. And surely, since you’re in a building, the giant worms can’t get close enough to affect anything. Plus, the number of banshees would be unchanged since 10 feet ago, as would the scry spell.
Unless OP’s players are just as unhinged, and spend a decent amount of time scouring every inch of the dungeon, ten feet at a time