Places of interest can crop up anywhere we need them to be. They can be created long after we’re already using our world or right from the first story. But if we have wars or battles in mind, we can start with these as sources of phenomena. Any fight involving titanic forces, like great magical or technological power, can be the instigator. Decide where you’d like this place to be, such as in a remote location or a central one that impacts life all around it, probably via avoidance; the latter will be a major factor in stories taking place near the location—remote locations give us leeway to invent places of lesser impact. If we have a goal in mind, such as wanting a point of origin for a monster, inventing the creature first can give us ideas on where and what caused it. If we’ve already invented several places, we can invent a different type of place, in a different location.
