Earth 60

In this reality, Earth was at least four times as large, and much of it has remained unexplored into the twenty-first century.
Technology and culture advanced to a level analogous to modern times before one was brave enough to try to cross the vast Eastern Ocean (an ocean estimated to be covering a distance of over 20,000 miles). When doing so, a massive landmass was discovered, similar to how European explorers rediscovered the American continents. The difference here is that the continent, dubbed Terra Pericula, was inhabited, instead of by cultures of humans, by monsters. It appears that at one point humans had inhabited the landmass, judging by the vine-covered ruins of ancient temples and the remains of massive underground fortresses (as well as the fact that zombies are commonly found there), but the only things that remain now are cannibalistic zombies, archery-skilled golems (rock monsters), and sentient plant-creatures who enjoy kamikaze-killing by way of blowing themselves up. They are known as Gaea's Warriors. Only the bravest (or most foolhardy) people risk trying to build a home in Terra Pericula by choice, however, occasionally people will find themselves stranded there by shipwreck or by plane crash, leaving them forced to try to find a way to survive.