After a slew of content from Bethesda for Fallout 4, the development team is finishing out March by releasing the beta for their new Survival Mode. The new mode was released on Steam today, allowing players to try out the update and test it before it is released in full on all platforms. Fallout 4 has had a Survival mode since release, however the old mode primarily upped the difficulty in killing enemies with few other features. The new mode adds far more factors to make the survival game lives up to its name, as well as increasing the difficulty and adding more realism to the experience. In addition to everything that wants to kill you dealing more damage, players will now have to account for fatigue and sleep, hunger, thirst, illnesses, a decreased and far more unforgiving carry weight, and more dependence from your companions.
Survival Mode introduces several factors that can impede your journey in the nuclear apocalypse. Keeping an eye on your hunger and thirst is not a new concept in the survival genre, but rather than just a general meter to keep up or die, not fulfilling your essential needs can effect your AP, your S.P.E.C.I.A.L stats, your immunity to disease (more on that later), before it ultimately starts picking away at your health bar. Sleep has become essential in the new mode - on top of being required to avoid fatigue and repair crippled limbs (which will no longer heal automatically after leaving combat), it is also the only way to save the game. There are a few autosaves left in the game (Bethesda doesn't say which, but it can be assumed they're autosaves related to large in-game events), so you should be prepared to take a nap nearly every time you find a bed or risk losing a lot of your progress on the certainly unlikely chance you die to one of the now more numerous things out to kill you. Especially since on top of it all, there is no Fast Travel, so if you die after a long trek, you'll have to make that trip again.
There's also the introduction of diseases, which must be cured with antibiotics (Stimpaks won't do the trick here), healing from items is lowered, and now everything, including ammo, will have a weight, and even your companions will be carrying significantly less.
Bethesda explains that they wanted to create a "circular system" similar to that found in Dark Souls where factors contrast and push against each other, forcing the player to find a comfortable balance. In this case, curing your radiation poisoning can open you up to disease, but your radiation poisoning will likely be worse because you must preserve Stimpaks more and you now have to eat and drink more often to avoid fatigue. All while keeping your inventory small to avoid the consequences of encumbrance. Even Bethesda staff are quoted in their release update saying the experience feels vastly different from the base game.
The mode is just out in beta and only available to Steam users currently, so bugs and balance issues may still pop up. Bethesda hasn't released an exact date for the full mode release, but if all goes well all platforms should be able to try out the new mode next month. Players who decide to help test out the mode can give their feedback through Steam or through Bethesda's community forums. Keep in mind if you decide to try out the beta, your mods will be disabled and you will be unable to load them (though there will probably be all new mods for this mode specifically by the time it's released so you can look forward to that).