Here's why Assassin's Creed: Unity is the first in the series to include co-op 

Assassin's Creed games have always been strictly single-player only, with the added multiplayer. Assassin's Creed: Unity is going to change that by being the first in the series to add co-op.

Senior producer Vincent Pontbriand spoke to CVG about the reasons behind the decision, "Because it's very complicated to do. Assassin's Creed was always a single-player game to begin with," he said.

"It took us three games to introduce PvP (player versus player). It was in the same universe but you were playing as a Templar avatar in a very separate game mode. In Unity, we set out to unify all these game modes into a single experience.

"That's when we decided that co-op should be the next main focus but in order to do that we had to rebuild all of our systems to allow them to be replicated over a network and working online. So it took years of development to reproduce and redraft all of our sandbox features for a shared online experience."

So there you have it, folks. What do you think of this explanation?