Soul Calibur definitely. Anyone who says it's too easy hasn't cranked the difficulty up all the way, and there's no way someone can beat Weapon Master mode by only button mashing. A lot of those challenges force you to look at the move list and learn new moves and strategies to beat an opponent, many of which you would have to extremely lucky to figure out by button mashing.I found it to be a very challenging game, and saw great reward in actually learning to use a character properly as it makes it much easier to beat the crap out of friends when you know what you're doing.