Rebel 11
Home
Rebel 11
Updated on 04/05/01
Rebel 11 is a collection of chess programs from Schroeder BV, of the
Netherlands. With this latest release, Schroeder BV is bundling
several playing and analysis programs together on one CD. They include
Rebel-Tiger II, Gambit Tiger, Rebel Century 3.0, and the Rebel Century
2.0 analysis engine. There has been more than a little confusion over
this mix of software, so the first thing I'll do is quickly
discuss each program, and what it does.
Rebel Century 3.0 is the latest incarnation of Rebel, and runs under
DOS and windows. The program is fairly similar in capabilities to the
previous version of Rebel (called Rebel Century). The main additions
are the new Century 3.0 engine and CAT (computer analysis tool). The
latter will probably be of most use to computer chess afficionados.
Rebel Century also includes previous versions of the Rebel engine
(Rebel 7,8,9).
Rebel-Tiger II and Gambit Tiger are both windows programs, that use a
GUI developed by Lokasoft. This GUI is used to run the Rebel-Tiger II and
Gambit Tiger chess engines, which are written by Christophe Theron.
Not only can this GUI be used to run the Tiger engines, but it can
also run the Rebel Century 2.01 windows analysis engine. This engine
is the first step toward a full windows version of Rebel.
Unfortunately, you cannot as yet play a game against this engine under
the Lokasoft interface; you can only use this engine for analyzing
games.
Furthermore, the Lokasoft GUI (also called ChessPartner) is capable of
using Winboard engines and another engine developed by Lokasoft itself
(this engine is called LChess). The Chesspartner GUI comes with
initialization files for crafty and gnuchess; you have to write your
own files for others (it’s not hard, but you do have to do a
little research).
Ok, are you confused by all this? I hope not.. The key thing to
understand is that you are getting a number of chess engines that run
under two different GUIs (one DOS based, and one windows based).
The Chess Engines
There has been a lot of excitement surrounding these engines, and I
think it is quite justified. The new Rebel Century 3.0 engine still
has an incredible amount of positional knowledge. My subjective
opinion is that there are extremely few (if any) people in this world
that could tell the difference between this program and a very strong
human player. While Rebel has always been a very solid player, there
were some games played at the recent World Computer Chess Championship
where it showed it was fully capable of giving up some material for a
promising attack. So this engine plays very interesting chess indeed.
If you want to know more about the Century 3.0 engine, I would suggest
that you read Howard Exner’s review on the Rebel site. I think
Howard did an excellent job of characterizing the behavior of this
engine. In fact, you can also find some other reviews of Rebel there
as well.
Of course, this version also has the multiple engine personality
feature of the previous version. This allows anyone the ability to
change the playing style of the engine, and save these changes to data
files. Thus you can download and exchange these personalities, and use
them for play, analysis, or engine vs engine matches. The Rebel web
site maintains a number of downloadable personalities that you can
experiment with.
The Gambit Tiger engine has received a ton of attention on the
computer chess bulletin boards. It is a dangerous attacker, and will
sacrifice material without hesitation if it can pry open lines and
squares around the king. Some people are saying that this engine comes
the closest to mimicking the later Mikhail Tal's playing style.
But just as Tal's sacrifices were not always sound, so is the case
with Gambit Tiger. And while this may sound negative, you have to
realize that when humans play, it does not matter whether the attack
is "perfectly sound", since very few people can successfully
find their way through the unclear positions that Gambit Tiger can
create. And even in computer vs computer testing, the great majority
of Tiger’s opponents have not been able to muddle through these
complex positions.
I have already used Gambit Tiger to analyze some of my tournament
games. Based on what I have seen, I think that this engine understands
sacrificial play better than any other engine to date.
The Rebel Tiger II engine has a similar style to its predecessor, but
is stronger. People know I am a fan of this engine, and there is not
too much more to say. It's a workhorse, and is well suited for
analysis of your own games. If you want, I would suggest that you read
my previous interview with Christophe Theron (the author of the Tiger
engines). Not only does he have an interesting background, but he is a
genuinely nice person too.
A recent update is also available (04/2001) for Rebel-Tiger on the
Rebel website. This update adds tablebase access and other algorithmic
enhancements to the Tiger engines, which results in stronger play. The
update also adds an interface to the DGT electronic board (which I
have not tried yet). There are many other minor enhancements as well,
and I would advise current users to get the update.
The bottom line is that you get a number of very high quality chess
engines for what you would normally pay for one.
The GUIs
Previous owners of Rebel will notice that the GUI for Rebel Century
3.0 has not changed much from it's predecessors. If you are a new
user of Century 3.0, and are used to windows programs, it may take you
a while to get used to the Rebel way of doing things. For instance,
mouse usage conventions are different from what you may be used to.
Like most playing programs, Rebel has both playing and database
capabilities. There are more database functions included in Rebel than
in many other competing playing programs. For instance, you can search
by position and material - most playing programs only support header
searches, although that situation is slowly changing. Rebel also has a
built in statistical chess tree, which is fairly advanced for a
playing program.
And speaking of chess trees, this version of Rebel has a new type of
tree called CAT (computer analysis tree). CAT is a potentially useful
tool for those that do opening research on the various chess playing
programs. It is a specialized chess tree that shows you which moves a
number of programs are most likely to play from a given opening
position on the board. It also shows the success statistics for each
program. To be honest, this feature is going to appeal to a small set
of users out there. But those that have been looking for a tool like
this will be very happy to have it. Nothing like it exists on any
other program at this time.
There are also a number of deep analysis features for over night study
of games (for instance, you can modify parameters in the engine that
make it more suitable for in-depth analysis). When analyzing a game,
Rebel still scores the player’s move, along with the
computer’s suggested move. The most likely variation to follow
is also presented for both lines of play. And this is the primary
reason I have for using this program. It is the only program on the
market that has this facility (Virtual Chess used to, but I think that
program is no longer in development). And while I think that the
mechanics for analyzing multiple games could use some work, I think
that the information presented will help those that are interested in
studying their own games. Users of previous versions of Rebel should
also note that the multiple game analysis feature does not work. So
you will be restricted to analyzing a single game at a time.
But I have really written a fair amount about the Rebel GUI in some of
my past reviews. If you want, you can look at the Rebel Century review
here.
The Lokasoft/Chesspartner GUI used for Rebel-Tiger II and Gambit Tiger
has also seen some improvement too. Readers of my previous review of
Rebel-Tiger may remember that this interface includes facilities for
playing against the computer, or with other people via the built-in
internet chess server (ICS) interface. This interface also has the
ability to connect two Rebel-Tiger users over any TCP-IP connection.
Thus, you can match up any permutation of computer and human players.
From a practical standpoint, the ICS interface is good (when compared
to a program like Blitzin), and supports a reasonable number of
necessary features. The only thing that I found myself wanting was a
seek graph (similar to the kind blitzin has). At the vary least, I
think the "sought" command should have been added to the
internet pull down menu. Although, the ICS interface has had quite a
number of improvements, and most of the things I commented on in my
previous Rebel-Tiger review (like being able to run Tiger while
playing a game online) have been addressed.
And if you really think about it, this GUI has the best internet
integration of any of the currently available playing programs. For
instance, many people like the ability of the program to play directly
between two computers over a LAN, without needing to connect to a
server. Chessmaster is currently the only other program to support
this feature. However, Chessmaster does not have the ability to
connect to an ICS, which is even more important.
There have also been numerous small tweaks to the GUI, and you can now
control the fonts individually for each window type (like analysis and
move list, for instance). The two dimensional boards are really
pleasing to look at for extended periods of time. In short, I think
that most serious chess players will be very happy with the visual
aspects of the program.
Opening book handling has also been improved over the previous
version, and you can even now import rebel MVS format books.
There are also some basic database functions for storing and recalling
games; these have not changed from the previous version. Possibly the
only missing feature here is the ability to do a search by position
(the Chesspartner GUI currently only supports a header search).
Chesspartner also employs its own proprietary database format.
However, you can import and export games in PGN format (this feature
also works through the windows clipboard); Chessbase cbf is also
supported as a read only format.
There is now a multiple game analysis feature, which can be used to
analyze any number of games in any number of databases. It also
supports a pawn threshold (like in Fritz’s blunder check), so
that if the score of the move you played and the move Tiger suggests
differ by some amount, then the analysis is written to the game score
as a move comment. I found this feature very handy for checking games
that I had played with Chessmaster, which puts each game in an
individual PGN file. The only improvement I could suggest here is for
providing the user the option to write the analysis as a variation
instead of a move comment.
As I mentioned previously, there is a windows version of the Rebel
Century engine that can be used for game analysis. You can use this
engine one of two ways. You can use it to analyze an entire game, and
specify a fixed time for the analysis of each move. Or, you can
analyze the current board position in infinite mode, which will work
in conjunction with Tiger, if you so desire. One nice feature is that
the engine will stay locked to a position until you double-click on a
new move in the list. But, for a number ergonomic and processing
reasons, you are best off just using one engine at a time. In short,
you do get a windows version of the Rebel engine, but it is not as
well integrated into the ChessPartner interface as a Tiger, or the
Lokasoft engine is. Posts on the Rebel board indicate that the plans
are to have a fully "ChessPartner compliant" version of the
Century engine available sometime in the future.
There is one area that the Chesspartner interface does need to address
still. And that is the addition of some sort of personality feature. I
think that this feature will probably come when the Rebel engine is
fully integrated into the Lokasoft interface. I say this because there
is already a windows tool for modifying Rebel personalities, and it is
included free on the CDROM. So I suspect that this shortcoming will
not exist in the next version. This is not to say that a person that
buys this program is without options for handicapping the play of the
computer. For instance, you can use the included Lokasoft engine for
this purpose, or a number of winboard engines too. Or, you can just go
to Rebel Century 3, and tweak personalities to your heart’s
content.
Summary
The main improvements in this release are in the chess engines
included with this package. Some people will be disappointed that the
windows version of Rebel has been delayed. But I think that there is
enough value here to interest most people – i.e. where can you
get three excellent chess programs for 60 USD? People that already
have Rebel or Tiger will probably be most interested in Gambit Tiger,
since it is very different in character from the other two engines.
And while the Rebel GUI has remained largely unchanged, there are
numerous improvements to the Chess Partner/Tiger interface, especially
in the areas of ICS play and game analysis.
Copy Protection
Must install from original CD, no refueling required.
