Our tomb scene.
We built a "sandbox" with cheap OSB board and 2x4's from Home Depot. Spray painted the top brown, to wash it out visually a bit. Filled it (once it was in the foyer) with dirt from the construction site outside. Linen strips were torn and stained to resemble blood and dirt. Accent lighting was placed under and above. You can kind of see the x-mas light strings under the linen pile in the background.