Hi,
As Yogi_Baar said, you can generate higher difficulties in single player. What needs to be stressed is that you have to have a *multi-player* character of sufficient level (20 for Nightmare, 30 for Hell). If you play a single player character completely through Normal and Nightmare, he will probably be about level 28 or so. So, to get that character to Hell, you would have to play your multi-player character more than your single player character. Kinda settles the question ;)
--Pete
As Yogi_Baar said, you can generate higher difficulties in single player. What needs to be stressed is that you have to have a *multi-player* character of sufficient level (20 for Nightmare, 30 for Hell). If you play a single player character completely through Normal and Nightmare, he will probably be about level 28 or so. So, to get that character to Hell, you would have to play your multi-player character more than your single player character. Kinda settles the question ;)
--Pete
How big was the aquarium in Noah's ark?