One of our biggest goals with Boundless is to make a survival system that is so complex that it provides massive immersion, but still makes sense without being frustrating. We have solved this by basing our design on how the world actually works outside video games. Rain isn't merely an aesthetic feature - explore the mountains while it's raining heavily and you won't only risk catching a disease in the cold, but you also might slip and break your leg, and believe me, a broken leg is definately a big deal in Boundless.
Eating, drinking and sleeping is a must, but not all fruits and mushrooms are edible. Knowing as a player which ones you can eat might save your life, but eating the wrong ones might just end it very slowly and painfully.
There will be many systems behind the complexity of Boundless (immune system, hunger, sleep deprivation, physical condition, hygiene, etc) to provide a proper depiction of realism, but this does not mean that the player has to understand and know them all.
Instead, our goal is that players will have to step outside the usual logic of games and instead apply real-world logic to their gameplay. You want to swim across a large lake to get to the fruit tree on the other side? Okay, but make sure that the water isn't too cold or you'll catch hypothermia halfways and die. Furthermore, just because you can eat something that grows on a tree doesn't mean you should. You probably also want to stay away from stale or dirty water, or your stomach won't be very happy.
We know that this game will not be for everyone, but we also know that this is the kind of game we have always dreamt of playing, and we hope that you will love it as much as we will!