All I gotta say is this is like MGS4, you think there's only one way to do things but there are actually many extra areas and things you can find.
I bet not a lot of people figured out the stuff you can do in the demo either.
****Spoiler Alert
The section in the Demo, you can go up the ladder at the out house that's like the miner's office and find a tape there which you can play back in the real game. You can call the Shibito at the area where there's a phone and have the shibito open up a locked door to answer the phone so you can get in later. You can push a kart to kill off shibitos and open up a door to obtain an archive item.
Reading the archive items gives you a better understanding of what had happened, much like the MGS codecs it's just a little something extra that makes you appreciate the game more. All the URL you find in the game are real. Check them out =)
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