In total there are 6 possible endings, the ending you get is determined by the decisions you made during the game.
Worst Ending To get this ending along with the 'This is the End' trophy you must allow ALL 8 friends (Matt, Jessica, Mike, Sam, Josh, Emily, Chris, and Ashley), to die. Do not attempt to save anyone who needs help.
Watch the video Best Ending To get this ending ALL 8 friends must survive. Below are the choices you need to make for each character to survive.
Ashley: Sacrifice Josh and not Ashley. When you hear a noise during Chapter 9 do not choose to leave the group and investigate. Do not open the thumping hatch if you decide to investigate.
Chris: Do not point your gun at Ashley during Chapter 6 but instead choose to shoot yourself in the head (this will not happen). Shoot ALL the enemies with the shotgun during Chapter 8 so Ashley allows you to enter the lodge.
Emily: Allow Emily to escape the room during Chapter 8 and do not fail the quick time events.
Jessica: Have Mike select the more dangerous paths during Chapter 4 so he is able to get to Jessica quicker and save her. Always choose the 'Hide' option in Chapter 10 and complete ALL the quick time events.
Josh: You need to find ALL the Twin Clues or Josh will not be able to identify his sister's tattoo on the Wendigo that will crush his skull.
Matt: While exploring Chapter 6 with Emily do not shoot the animals that are roaming around the area. When you are on the radio tower select 'Jump to Safety' and do not help Emily. To help Emily you need to have the flare gun with you.
Mike: When Sam is given the choice to either 'Save Mike' or 'Hit the Light' selelct 'Save Mike' and then hide before running towards the light.
Sam: You must not fail any quick time events and you must successfully hide from the Wendigos.
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