I feel like adding a stable multiplayer game-play will improve the games overall sales, not just that but possibly making this a fantastic co-op based game. Friends can explore and share experiences, having fun at the same time. I think not a full fledged multiplayer game but a 1-4 player co-op game. Friends exploring caves together, getting scared together, and the overall experience would be outstanding.
Although this game will be released about 3 hours from now, I want to see how much people agree with this statement.