What's the recipe for making a historically world-class apex predator? In the case of Alexander the Great, it might be the three Ns: Nature, Nurture, and Nepotism.

Pagan Viking Sea Kings spend the 10th and 11th centuries morphing into Christian monarchs. But with rulers like Harald Bluetooth and Svein Forkbeard it's debatable whether things will be any less horrific for Scandinavia's neighbors