One of my greatest joys in gaming is the feeling of discovery one gets from exploring a finely-crafted world. When a world is designed properly, it can really suck you into its setting, and when you have the unrestricted freedom to explore its boundaries, you get a strong sense of place in the environment. It's not merely the sightseeing that makes exploration compelling -- it's the rewards you receive for your discoveries, whether they be little treats left by the developers or just the psychological gratification you get for finding a more efficient path.
Some of the real fun, however, comes from discovering tricks that the developers neither intended nor anticipated, like backflipping into an exploding bomb to reach a high ledge in Ocarina of Time, or planting mines on a wall and climbing up them in Deus Ex. These discoveries are more fascinating to me because they're completely unscripted. As rewarding as it can be to bomb a cracked wall in The Legend of Zelda and find a wealth of hidden goodies inside, it's really just a scripted sequence designed to happen in a precise way. There are obvious clues telling you what to do, which make these discoveries a little less personal and a little less dramatic.
Exploration plays a prominent role in non-linear, open-world, free-roaming sandbox games. Much of the appeal stems from the player's freedom to go off and search for adventure in his own way, but some games promote and reward exploration much better than others. Playing Risen 2, I've noticed that the exploration is at times very creative and satisfying, and other times it's rote and boring, which got me thinking about the broader picture on how games can design worlds that beckon for a deeper, more personal level of exploration and discovery.






