Avoid this game at all costs!
Magna Carta is not even mediocre, it is just flat-out BAD! RPG fans, run from this game for your life! It may look pretty and have girls with big boobies on it, but it's horrible!!
Cons: Where to start? The worst thing is the battle system. You can only control one character at a time, while the others just stand there and get killed. They don't even move away from the enemies attacking them! You have to keep switching between your characters just to stop them from standing there like dumb hunks of meat. Blech.
I also personally did not like the characters much, and found the game's "story" quite boring. I stuck with this terribly broken THING for a while hoping it would get better, but it did not.
Pros: Only thing I can think of is the graphics, they are decent. If you're a guy, you will probably like the girls in this game, but that's a sad reason to get it.
DON'T buy this game just because it is from Atlus and may become rare. In this case, if it became rare it would save many people from getting lured in by the beauty, then smacked by the horrible gameplay. There are many other actual GOOD Atlus games.