A:AnswerYou do not, I played the whole game without one. The subscription is only required if you want to play the online mode where you see player messages and can be invaded/invade others.
A:AnswerIt doesn't come with the DLC, so you'd have to buy it separately or instead purchase the Game of the Year edition. I will say that if you want to play it, I highly recommend purchasing the DLC before finishing a playthrough since it automatically puts you in NG+ upon beating the game.
