I can't seem to find a description on how difficulty works in T2. I'm playing on Casual now, with the thought that I could then start a new game + on Normal, play through again, and then maybe do another new game + on the next difficulty. However, I'm hearing rumblings, that when you make a character, you're locked into the difficulty you create them on. Also, how does difficulty scale for multi-player? If my character is Casual, and my friend is Normal and we play a game, will it just match the difficulty of the player who creates the game?

Sorry if these are stupid questions and I'm just missing something obvious.

You can change difficulty on multiplayer games (there's a drop down menu when you create a game), not sure how that will affect your single player experience though.

Also I would recommend playing on Normal for easy mode, unless you have literally no previous gaming experience.