They walk through the darkening forest. The bare branches are reaching towards them as they scramble through. The wind whistles through the trees and they hear faint words being spoken. They come to a bare patch of ground that is clear of bushes and brambles. Across the clearing is a crumpling ruin that looks quite ancient. Long-forgotten gods crumble at the entrance and the name of a long dead emperor is etched above the door. When they enter they hear scratching sounds. The walls are covered in unknown languages that could be invitations or warnings. Deeper into the winding ruins the scratching sounds become louder. Long dead humans begin to scramble toward them. The skin has fallen from their faces, their bodies are decaying, and they are covered in tattered shrouds. The monsters mouth soundless screams and begin to give chase.
Simply saying a forest is haunted is not enough. A DM must give details that pull their players into the scene so that they can picture smelling the trees and feel the anxiety creeping in. Olla's scene written above is a shining example of what this generator can do for your next campaign.