All games are occult. We as players are not privy to the inner workings that define the rules by which we play. Unlike in a tabletop RPG, we're not even aware of the dungeon master's screen that hides the game's secrets and mechanics from us. Still, few games turn the inherent occultism of the medium into their central theme by making us acutely aware of the presence of the invisible screen, compelling us to piece together a mosaic of uncertain knowledge. And only an elect handful does so while invoking age-old traditions of magic and esoteric philosophy.
The most well-known of these is Bloodborne, a game which is notoriously obtuse and unwilling to reveal its hidden depths to the player. While deadly creatures may seem like the most obvious danger, it's ignorance that will be the biggest hurdle to the inexperienced. To glean some of the knowledge necessary for progress, intrepid hunters will either have to study the game's world closely or rely on the information collected by more experienced hunters.
The in-world representation of this striving towards understanding is the resource called "insight," inhuman knowledge gained by laying eyes on or defeating certain enemies as well as consuming items like "Madman's Knowledge" or "Great One's Wisdom". The item description of the latter tells us: "At Byrgenwerth Master Willem had an epiphany: 'We are thinking on the basest of planes. What we need, are more eyes.'"