Over the last many hundred thousand years, civilizations and species came and went. They have left Earth with ruins and remnants hidden beneath the sands, with whole cities long reclaimed by the unforgiving mud that, in the end, consumes all.

A quick sketch, obviously out of scale, of the arrangement of the most important “archaeological” layers of the highland regions of Gog. (click to enlarge)

Working with the timeline a reverse chronology of the world presents itself in the many layers of rubble. As there is little plant-life present in the highlands of the Magog empire, solid earth is scarce. Dust covers ancient debris, often carried away by the wind, and the stones themselves have been polished by its gnawing tooth. Where in other places many hundred meters of mud would separate the layers, on the highland plains of Magog they lay in close proximity. Digging through the ruins from the surface down to the abyss will go through the following layers of civilization:

• Surface: Steppe, rocky deserts, meagre grazing lands used by the nomads. Amidst these, roads and walled cities of the Magog. A few construction sites from the time of the explanetarians remain visible, half-buried as they may be.
• Just below the surface there may lay ruins of the green-skinned Arraqu’s exorcist priests old monasteries, abandoned due the encroaching empire. Destroyed rebel settlements, military buildings and smaller city-states that fell in the 600 years since the establishment of Gog could be excavated.
  This level would contain the main hubs of the few explanetarian sites, where machines may still be intact. The human Magog will find they respond curiously to their touch.
• In the western part of the highlands, maybe two millennia from today, the civilization of the arachnid race fell in mutual genocide with the explanetarian settlers. Tomb or honey-comb like structures are found about 40 metres below the earth in some regions (or, in some cases and especially alongside the Rift, carved caverns into cliff-sides). Of course most of these would be found in the regions that fell victim to the irradiating star-light weapons of the explanetarians. The oldest explanetarian sites were established somewhat later, but reach down to this layer due to their deep foundations and for fortification reasons.
• Deeper still, and often serving as the rubble upon which most of the modern world stands today, await the the abandoned pyramids from the Age of Snakes. having served as masters for hundreds of thousand of years, they cover many layers of what was once the surface, and bizarre geography abounds, misshapen by sorcery in war against the planet’s former inhabitants. Many pyramids still stand, desolate and empty – the escaped post-human slave races often dared not return to the cradle of their suffering. Some were plundered by the arachnids, barely able to make full use of the powers at their disposal. A few explanetarian sites – most notably the great “bottomless” pit in the center of the city of Gog, once planned to be a core mining operation – may have found their way into this layer.
• Twisted layers follow, as the Snakes reshaped Earth to suit their needs. As the former Snake masters withered away, secluded from their brooding worlds, some of their enslaved beast populations and demonic servants may remain in hiding. Everything is possible in that now-entombed world, for the chaotic magic has left its stain.
• Deeper still, destroyed unfathomably long ago, some remnants of the space-faring age of Homo Sapiens Sapiens may remain to be found.