Playing games is largely a process of exploration. Often this is in a very literal sense, where you’re given a simulated physical space and part of the challenge is learning the ins and outs of it, but just as often the heart of the game lies in exploring the the edges of the game’s design or of its story. What actually is exploration though? What separates exploring a world from merely experiencing it? How can we support exploration, make it fun and interesting? Or, perhaps more saliently, how can we avoid undermining exploration without meaning to?
There’s two parts to exploring: Methodology and results. Methodology is what separates the process from pure random trial and error – even if you feel that you are wandering aimlessly and finding things as you go, you’re still building up an understanding of the environment in your head and applying that towards your movements. At the very least, you avoid exploring areas you’ve already been through in favor of finding new areas. Results are whatever you get using your method of approach. So, when we’re designing for explorability, we must have both a world that is consistent and predictable, so there can be method to measuring it, and a world that contains interesting things worth discovering. There is also a prerequisite to exploration: In order for something to be revealed, in must first be concealed. In order for it to be discovered, it must first be covered, so the world must also have parts of it which are not immediately obvious.
If you lack consistency of world, then surprises come randomly and without justification, and the player tends to meander interminably before finding anything of interest. If you lack anything worth discovering, that’s obviously even worse, and if everything is already obvious then there’s nothing to find. As an example, if you create a world that’s continuously being randomly generated, it might be an interesting experience but there’s no way to effectively explore it: methodology is useless, the discoveries pointless, and you could never expect to have any more knowledge of the world than one had first coming to it, meaning a world completely uniform in its inscrutability, an open book containing nothing but nonsense. This conflict between randomness and exploration is one reason why games attempting fusion of the randomized worlds of roguelikes with the exploration-heavy worlds of metroidvania tend to succeed far more as roguelikes than they do as metroidvanias.
In creating a simulated physical space to explore, using these concepts of methodology, result, and concealment is a pretty straightforward task to grasp. First, make it so your world has some logical spatial relationship – most games are like this by default, since they’re built on modeling a 3d space, though some like text adventures struggle a bit and map transitions can always throw a wrench in the works. Note that this is not to say you can’t or shouldn’t have weird and impossible architecture, just to note that the more confusing and counterintuitive it becomes the harder it becomes to effectively explore the space, which may or may not be something you want. Second, make the world also have things worth discovering: In purely spatial terms, this would just be an interesting location such as a cave or grove, but more practically this is where the ‘physical’ space of the game starts to overlap into the design and narrative spaces, since most actual interesting locations in games are interesting either because they contain gameplay advantages such as powerups or tactical positioning or because they contain narrative content such as historical information or new characters to meet. Third, make it so it isn’t immediately evident where these points of interest are – this is why having things like minimaps, fast travel, and x-ray vision can work against the sensation of exploration, since providing this information directly often works directly against concealment. Too much information is provided for free, so there’s no real room for method to beget discovery.
So, carrying these concepts over from the spatial realm to the game’s design, if we want to have an explorable design space it must be, first, consistent: This, like spatial consistency, tends to come for free in a highly systemic game but become scarcer the more separate systems or special exceptions exist. If every game element exists within a consistent system, people can devise and improvise interactions, can plan out experiments and log their results. They have a territory to map. Second, the game’s design must have things worth discovering – understanding the bounds of the design is usually a core part of what it means to become better at a game, so this is covered as long as the game’s challenge isn’t trivial. This is part of what difficulty offers us, is a system worth exploring. Third, the system must not be obvious, must conceal parts of itself: This is one that a lot of modern games struggle with. There’s a tendency to clip off surprising and unexpected parts of a game’s design, to ensure that the experience always feels ‘fair’, to set the boundaries of the design strictly at those of the developer’s imagination. It seldom works completely, but to the extent which it works it impoverishes the game.
Narratively, the tenets of explorability tend to resemble a great deal of existing storytelling advice. Avoid plot holes and give characters motivations to create a consistent narrative reality, include drama, jokes, and surprises to generate interest, and don’t lean on cliche and trope so much the entire arc is obvious from the first moment.
As mentioned earlier, these spaces all overlap. The surprises you discover in the spatial layer may have implications for the design, the techniques you discover in the design layer may have implications in the narrative, the story you uncover in the narrative may lead you to new places in the spatial. These aspects are all woven together, and the ability to uncover them collectively is one of the greatest things games can offer as a medium.