7. Victorian London
While the NPCs are shockingly thorough, the real non-playable star is Victorian London itself. The environment is incredibly well designed (clearly a mountain of attention has gone into the art direction). The environment is so easy to get sucked into, and as Vincent Vega once said: 'It's the little differences' walking through streets as people flee in terror, or bolt their windows and doors shut at the very sight of you, is something we wish could be a part of every single game in the history of the medium. The alternate history aspect is seamlessly implemented into the design of the world. London is still London - there aren't any insane, out of the ordinary buildings or people that would be better fitted to a more traditional sci-fi game. The industrial revolution is a perfect cloak for the slightly steam-punk influenced touches - zeppelins, complex weaponry and ornate decoration. It sounds silly, but even the level of detail in doorways, shop windows and the haphazardly paved streets themselves is unbelievable - above even Assassin's Creed levels of attention to detail.