 If a survivor falls off a ledge, then they may automatically hang onto it and can only be helped up by another survivor.If a survivor's health is depleted, then they become incapacitated and can only be revived by another survivor, at which point they continue playing with a low amount of health that decreases over time.If a survivor has been incapacitated and revived twice without tending to their wounds, then they will experience distorted black-and-white vision, and the next incapacitation will kill the character.