Sierra On-Line set a lofty goal for this second edition of its Power Chess series: to create a computer opponent who plays chess like a human. And we're not just talking about designing the AI so that the computer foe - called the Power Chess King - makes a few mistakes now and then, either. Sierra claims that the Power Chess King's "mood" changes throughout the course of a match based not only on a slew of variables such as how well the pieces have been developed and how exposed his king is, but also on how he perceives those variables.
Power Chess' online manual has a fairly good explanation of how it works, chock-full of words like "hysteresis," "tropism," and "rexotropic." But in the end, only one thing matters: Does it or doesn't it play like a human opponent? I can't claim to be an expert on such matters, especially considering that I'm only a middling pawn-pusher, but after many matches with the King, I'd have to say its play does exhibit some of the hallmarks of a human.
If the King is pressing to finish you off quickly because of a weakness he's detected in your position, for instance, he'll sometimes miss the best move - perhaps a move that would reward him with a nice gain in material. And even if you've fallen far behind, you should never give up against the King unless the situation is extremely desperate: In several matches where it looked as if my defeat was inevitable, I turned the tables and found the King begging for a draw!
Of course, other chess programs have weaker opponents that will miss moves and pursue recklessly, but the difference here is that the Power Chess King has been designed to adjust his play to your level. As your Power Chess rating (not to be confused with USCF or FIDE ratings) increases, his play becomes stronger. So while I enjoyed victories in my first two or three outings, things got a lot tougher in very short order.
After each match with the King, the Power Chess Queen - backed by the impressive WChess engine, which scored a win against Deep Blue three years ago and has defeated several US champions - will analyze the game for you. It's up to you just how deep her evaluation is, and it's delivered in a voice that's almost a little too sexy for its own good: Every time the Queen speaks, I think I'm about to hear a pitch for fat-free ice cream or a Lean Cuisine dinner.
In addition to the King, you can also play against the Queen, the Prince and the Princess (they play at the difficulty level of your last game with the King, except the Princess will use the WChess engine in the "middlegame"), the Nobles (opponents you've created by determining aggressiveness, speed of play, and other factors), and the commoners. The 20 Commoners are precustomized opponents ranging in strength from very weak to nearly as strong as the Queen, with each sporting a distinct style of play. Seven of the commoners are based on famous chess luminaries, including Anatoly Karpov, Yasser Seirawan, Bobby Fischer, Judit Polgar, and Mikhail Botvinnik.
There are a few problems in execution in Power Chess 98, some surprisingly basic in their nature. One of the most vexing is that you must always use the funky "Fischer clock" when playing against the King (it adds a certain amount of time to your clock when you make a move) - not exactly the best way to prep for an over-the-board match with a human, where the Fischer clock is almost never used. Other annoyances include the absence of a "force move" command to hurry up a dawdling computer opponent, interminable load times (due in part to a "King enters room to play" animation that you can only skip once it's onscreen), and the inability to use clocks during Internet play (more about online play later).
Still, there's no denying that Power Chess 98 is an exciting and unique chess program. For me, though, the biggest factor in deciding which chess program to buy is how well it helps you learn the concepts of chess and improve your play - and here Power Chess 98 takes a backseat to Chessmaster 5500, the reigning champ of chess programs.
All you get in the way of tutorials, for example, is a hypertext version of Advanced Strategies: My System by Aron Nimzowitsch. It's an outstanding book, to be sure, but no attempt has been made to make use of the power of the computer: There's no speech, no moving pieces - nothing more than a copy of each printed page. Compare that with CM 5500's 26 chess tutorials - some featuring multimedia presentations, and all of which are subdivided into very specific categories - and it's easy to see which program comes out on top when it comes to exploring and explaining the various aspects of play.
For chess lovers, there's nothing like poring over some of the classic games that have been played over the years - but aside from 50 illustrative games in Nimzowitsch's Advanced Strategies, you only get seven classics in Power Chess 98, compared with hundreds in CM 5500. It's true that nearly all of CM 5500's games feature text-only annotations, as opposed to the lilting voice of the Queen describing the seven classics in Power Chess, but CM 5500's auto-annotate feature means that any classic game can be annotated with voice narration.
Then there's analysis of your games. I'm not certain why the developers decided to only let the Queen analyze games you play against the King, but in my opinion it was a bad move: Who wouldn't want her expertise regarding games you've played against a human opponent or against one of the other computer opponents? Power Chess 98 does have an analyze-game feature that will evaluate the moves in any game, but it's text-only and presented in a format that's much more difficult for beginning and intermediate players to understand than the spoken auto-annotation in CM 5500.
One of the most crucial keys to improving your game is mastering the myriad opening move sequences - collectively called the opening book - and here again Power Chess 98 takes second place to CM 5500. To put it bluntly, there simply isn't an opening book where you can study the thousands of opening lines developed by players over the years.
The computer opponents in Power Chess 98 use many openings, but you're never told what they are; instead, the game encourages you to master a single opening, the Giuoco Piano, but no matter how much I scoured the documentation I could never find a single instance where the actual moves of the opening were shown! Instead, you have to listen to the Queen's advice after a game with the King - she constantly coaxes you into using it without ever saying what it is. It just doesn't compare to the over 2200 opening lines included in CM 5500 - and a feature that automatically displays the name of the opening being played by an opponent during a game. Last is Power Chess 98's multiplayer feature. I'm extremely appreciative of the inclusion of support for Internet play and in the past have lauded Sierra for including it in its games. But its importance in Power Chess 98 is blunted because you'll only find a handful of players on Sierra's WON (World Opponent Network) as compared with hundreds and sometimes thousands on The Chessmaster Network for CM 5500, which also features its own rating system for Chessmaster Network players (you do have to pay a yearly fee to be rated on the CM Network, however).
What Sierra's achieved with Power Chess 98 is no mean feat, but in looking at all the stuff that's just not here it seems that the quest to create a humanlike opponent came at the cost of some fundamental features. If Sierra can up the ante in terms of tutorials, game analysis, and openings, the next Power Chess will have the stuff to challenge Chessmaster 5500 for chess supremacy.