World and levels › The idea
Open-world design: regions and landmarks
Know first: World scale: meters, minutes and density
What pulls a player forward in a world where they can go anywhere, with no arrows, no lines on the ground and no markers? It starts with the map a player builds in their head, and with regions that each have a character of their own. Landmarks that show from far away, hills that hide and reveal, and buildings of different prominence that lead players off to the sides do the rest. So does the emptiness between events. The examples are Zelda: Breath of the Wild, Ghost of Tsushima and Firewatch.
Why this matters
In a corridor level there is one path, and the designer knows where the player will be in a minute. In an open world the player is free to go anywhere. That is freedom, and it is also trouble. If there is nothing to look at and no reason to go anywhere, a huge world turns into a field that players trudge across toward a marker on the map.
Think of a city where you can find your way without a map. You know its districts: the old center, the industrial zone, the residential blocks. You know the main streets and squares, the tall buildings seen from everywhere, the river that cuts the city in two. That is how you know where you are and where to go.
An open world is built the same way. Its job is to let players assemble a map like this in their heads and want to go further on their own. An arrow on the screen does that work for the player instead of letting them do it.