Well this was a surprise. Not sure why Ubisoft wouldn't announce this at their conference but Assassin's Creed: Odyssey is getting a new way to play the game in the form of the story creator.
The story creator looks pretty in depth an allows you to create your own branching story lines for Assassin's Creed: Odyssey including what character to use, what enemies and you can even add your own dialogue as well. Best part is that your creations can be uploaded and shared with everyone else and you can download other quests to your game as well. It's also free for all players.
To use the story creation tool, head over to the official website.