It includes every possible situation - indoor, outdoor, underground, alien environments. The emphasis for this tutorial is fantasy, vs any other genre - even though every genre will be covered eventually, I'm trying to stay generally fantasy since the bulk of the player base involves fantasy settings. The suggestions offerred so far include: a pile of stones that can be built larger or smaller with the same components, seige machines (probably hinted by the use of a trebuche in the example), torture devices (rack specfically mentioned). I am open to any general use object that can be commonly used in many games. So any one of these suggestions work, but is there a better, more general choice?