Couple that with the fact that enemies don't appear on the game compass and are tougher in general that unrevived companions won't respawn and ammo will weigh more depending on its caliber. If you want to get somewhere you'll need to travel by foot, which means lots of random encounters with enemies. You'll need some antibiotics to be cured. Oh, and if you eat bad meat, get a disease or use Chems, you might get sick. You'll need to sleep, eat and drink regularly or your SPECIAL stats will reduce, you fatigue will increase, and combat in general will be harder because of it. Of course, you still can't sleep when enemies are nearby, but the mechanic is changed slightly still: sleeping bags, for example, won't let you sleep through the night and improve your health, but they will let you save the game. The only way to save in Survival Mode will be to sleep. The biggest changes concern saving and health. As VG247 reports, enterprising Redditor ShaneD53 dug through in-game files to pull out text pertaining to the upcoming game mode and got a lot of info. Fallout 4's Survival Mode isn't going to be pretty.

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