How do you adjust the campaign difficulty while playing 2-player local?
Can it be done in the Master Chief Saga playlist or is it for the individual missions only?
You cannot change the difficulty for the playlists. They are using premade seetings. If you want custom setings you have to go the the campaign selection.
Would be cool if you could change the difficulty for some of the playlists. Normal is a tad to easy for me but ohwell. Still want that saga playlist complete 
I wish you could change the skulls/difficulty. 