I'd like it to be single player though.
Imagine playing a game of chess, where every other move, a 9 year old has to take your turn. Any strategy, plans, whatever you had, throw it out the window, because every other turn, someone else with no knowledge of what you're doing is going to be making the next move.
I was fortunate that my teammate Absol didn't really have an interest in playing, and dropped out a few games in. Don't get me wrong, I don't mean to say that Absol's an idiot or anything like that! ( Darkness nubs 4eva <3 ) The idea I mean to get across is that you really can't have this type of game being played by a team. It just doesn't work in my opinion.