In the original game i remember being able to chose hard difficulty from the first time i played a mission. Now however the only available difficulty in the first main mission i tried was "story". Hard and normal were unlocked after completing the mission in the replay option. Is this how all the main missions work? Do we have to finish the campaign in story mode before we can jump in the harder difficulties or is the hard mode unlocked after a certain level? Also is there no difficulty option for side missions or open world exploration before the endgame? Finally does the world and missions scale with your level like in Assassin's Creed Odyssey or can we over level activities?