So from what we can gather it's a stealth exploration / survival game with some kind of combat system. The vague objective is to traverse Scandinavian highlands to obtain stuff, that stuff including resources and bodies. Exploration includes complex terrain navigation thus using tools when necessary, eg rappel up mountains and use artificial bridges to cross ravines. Transporting items/goods is done in real time and there appears to be various ways to accumulate and carry more goods, either on the player avatar or via assistance (like transport trollies). Scavenged goods can be dropped if the player makes a mistake, such as getting caught in a rapids. Navigation also may include vehicles, such as what looks like a futuristic motorbike, and standard vehicles in the previous trailers.
Something has happened in the game world, such as the invasion of some creature(s), that have disrupted the link between life and death and passage of time. The world has been disrupted, natural order of the oceans and living creatures disjointed, such as causing whales to beach. These creatures appear as invisible or phasing ethereal beings linked to something via ghostly umbilical cords, and prey on the living. Their contact with objects speeds up time, such as causing a person to rapidly age or plants to rapidly grow and/or die. Of note is rain, as when it rains this seems to trigger the appearance of these beings.
Scavengers have access to various tools and equipment that allow them detect the unseen creatures. The key tool is a mechanical light flower linked to a baby in an artificial womb. The babies appear to have a natural intuition and sense for these beings, and when linked to these lights allow said lights to point at, flash, and respond to the presence of invisible threats. Staying silent and showing no sign of movement is the best means of avoiding these creatures.
The protagonist, Sam, seems to have the embodiment of one of these babies existing within him. This differs him from others as while they are reliant on tools, Sam can naturally "sense" them, and when using the tool have a better approximation of their location.
Being caught and consumed by one of these creatures has an unspecified impact on the living, perhaps tethering to the world in ethereal form transformed into another threat. Sam's unique abilities prevent him from ever actually "dying". When captured by the beings Sam will "revive" back into the world, coughs up unusual insects also seen being eaten by another character, but a cataclysmic event will occur leaving a crater at the location of capture. Thus Sam appears to not only have an intuition in detecting the presence of these creatures, but also seems to subvert their unusual engagement with the passage of time, breaking the life/death cycle and tethering to an undead ethereal world. Other individuals who do not have this ability appear to prefer death at their own hands or others than get captured.
There appear to be numerous organisations involved in the scavenging of these lands. Among them include BRIDGES and FRAGILE. Their purpose and affiliations are unknown. Seydoux's character works for FRAGILE, and appears to wear a suit that responds with physical alterations to the presence of the beings. Mikkelsen's character wears military attire, and seems to have some kind of artificial emulation of abilities similar to that of the beings, able to utilise the tethering of life/death and unusual manipulation of beings (eg: reviving the dead).