While exploring, he and a friend discover artifacts of an alien civilization, including a working land vehicle that has legs, like a large metal centipede.

Their rarity and superiority has sparked suggestions that they have been made by an advanced ancient alien civilization or by coming from the beginning of the universe itself.

More hypothetically, advanced alien civilizations evolve beyond broadcasting at all in the electromagnetic spectrum and communicate by principles of physics we don't yet understand.

With her aid, he would acquire technology from alien civilizations, which would automatically give him advantage over the contemporary human military forces.

Wars between separate alien civilizations are featured.