Praying to yourself, my Lord? That's not a good sign. Or perhaps it is. Prince of Madness, and all that.
Madness string 3747
If vampires don't need air, they would be awesome scuba divers. They could just wear a backpack full of rocks and walk on the bottom. And if they dive deep enough, light won't even reach down there. Like, aquatic vampire covens at the bottom of ocean trenches...