Non combat poltergeist actions.
I love horror flicks, and I get lots of GM inspiration from the scenes leading up to the monster's arrival. Wanna watch a great haunting? Watch the coming of Jacob Marley in Christmas Carol.
The door knocker becomes Marley's face.
Marley's chains are heard dragging up the stairs.
Marley bangs on the door, but with the force of ten men.
The door swings open, and winter rushes in.
Marley walks in, dragging his heavy chains.
But he cannot speak.
Marley must unwrap a bandage around his head, and his jaw drops open...like a corpse.
For me, OD&D is fantasy horror. I am all about magical monsters being supernatural, otherworldly and infused with the same reality bending power we see in movies.
For me, a dungeon is a haunted house.