Here's the new paper terrain piece I made: it's a small obstacle, the ruins of a burned house or something like that.
The base was made as usual: EVA foam covered with suede paper. The burned wall was built with a piece of black cardboard, folded in an "L" shape. Strips of wood-textured adhesive film were placed over it, with a 1mm space between them, to make them look like wooden boards. After this was done on both sides, I cut an irregular profile to simulate the burning and applied some acrylic dark brown paint on the "burned" edges.