Horde Mode and Multiplayer Options

Multi-player mode is huge in the game industry. I think it would be possible to have at least one other player in story mode. We only have one Protagonist and she is the one we play through the story but Fable solves this by making the second player into a limited action character. For example, the second player can fight enemies with you or for you but cant unlock doors or talk to people.

Here's a bit of the multi-player game play of Fable 2.

Horde Mode co-op is also becoming a huge trend, games like Gears of War and Left for Dead being the reason. It would be great if we could create such a mini game outside of the open world story mode and create small maps in which you and 4 other friends can fight horde after horde while trying to get to a certain point for example. So, you can unlock achievements without going back into the open world and get into more side missions. Sometimes I just want to fight!
Here's game play of Horde Mode in Gears of War 3.

At one point we were talking about the sangria drug causing side effects and when mixed with the blood of aliens one will gain their powers. We could have these people as hordes in this game mode.
Here are some of the Gears of War Monsters: