Primordia

 
What happened to the humans? 
Set in a post-apocalyptic world strewn with cast-off machines, Primordia tells the story of Horatio Nullbuilt, a stoic robot who values his solitude and independence. Horatio spends his days studying the Book of Man, sparring with his droid companion Crispin, and tinkering with the airship they call home — a peaceful existence that becomes threatened when a rogue robot steals the energy source that the pair needs to survive.
When Horatio and Crispin’s search for energy brings them to the dazzling city of Metropol, the simple quest to recover their stolen power core leads to unexpected discoveries about Horatio’s origins and a new understanding of the legendary humans who walked the earth before him.