Publisher: Open-source freeware
No discussion of Diablo or its sequel is complete without a passing reference to NetHack. The fact is that comparing Diablo to NetHack is like pitting a wading pool against the Marianas trench; the former is fun and gives you a taste of what the real thing is like, while the latter is immense and deep enough to crush visitors who venture in unprepared.
NetHack is a spectacular dungeon crawl that has been in development for more than 15 years. It's the only game in this feature that we can refer to in the present tense, because it is the only game still being actively worked on. It features random dungeons, enough monsters to fill an AD&D menagerie, and enough commands to create a programming language. The only problem? NetHack has no graphics. Instead, it uses ASCII text characters to depict all the game objects. The character is represented by an "@" character; gold is the "$" symbol; walls are created using dashes and pipes; and various monsters are represented by letters of the alphabet.
Purists will argue that the ASCII-based Rogue belongs in this spot, but NetHack (which is based on Rogue) is the ultimate incarnation of that older classic. It has a more active user community and vastly improved gameplay, and it gives you many more things to do.
Take the character classes, for instance. NetHack lets you slip into the familiar roles of monk, barbarian, rogue, knight, priest, and wizard, but that's just the tip of this very cool iceberg. How about playing as an archaeologist, who uses his or her knowledge of dungeon lore to conquer a dungeon? Experienced players can have a lot of fun as the tourist, a wimp who starts the game with loads of cash, a credit card, and a camera. There are many more classes beyond those already mentioned, including the unique caveman and samurai characters.
Then there are the sheer number of commands and options available to you. Nearly anything can be picked up, combined with other items, and used in unusual ways. You can hop on the backs of some of the monsters and ride them around the dungeon. Some versions even let NetHack interface with your e-mail inbox, so if messages arrive while you're playing they are hand-delivered to your character (in the form of a readable scroll) by a mail daemon.
Most gamers avoid NetHack because of the ASCII graphics, but in many ways they enhance the gameplay. After a few hours, as you become more familiar with the meanings of various numbers and letters, NetHack begins to take on a life of its own. That gray "B" (vampire bat) chasing your "@" is much more nightmarish when your imagination is supplying the visuals. In fact, we played a version that adds tiled color graphics to the game and found that it ruined much of the tension of the ASCII original. Still, the graphical version is a great way for beginning players to see what NetHack has to offer, and all Diablo fans should give it a chance to see just how rich a game of this type can be.