You are on the backup site for Any posts, moves, or other changes you make here will not be permanent, because the pages and database from the main site will be backed up here every midnight EST. Additionally, things may not be working right, because this site is also a testbed for newer system software. So, if you are not here to test, develop, or merely read this site, you may want to change .org to .com in the navigation bar and go to the main site.

The Chess Variant Pages

[ Help | Earliest Comments | Latest Comments ]
[ List All Subjects of Discussion | Create New Subject of Discussion ]
[ List Latest Comments Only For Pages | Games | Rated Pages | Rated Games | Subjects of Discussion ]

Latest Ratings and Comments

Later Reverse Order EarlierEarliest
Shatranj With Different Armies. (Updated!) Like Chess with Different Armies, but for Shatranj.[All Comments] [Add Comment or Rating]
Greg Strong wrote on 2022-05-27 UTC

Shatranj with Different Armies. Possibly a worthwhile idea... Only possibly, since Shatranj is such a bad game. I will digest this more and post further thoughts, but my first observation is that "The Japanese Jostlers" show a different icon for the Pawn, although the text claims it isn't a Shogi Pawn. Please clarify. Furthermore, I think Shatranj with Different Armies should follow CwDA in the core tenant that the Pawns and Kings don't change between armies. If you have armies with wild pawns, to me that is not "Shatranj with Different Armies" but something else.

Fergus Duniho wrote on 2022-05-27 UTC

I have published this. I would recommend using P for the Pawns and another letter for the Berolina Pawns, since if this game is ever programmed for Game Courier, every piece will need to be identified by notation.

Space War Chess. Game with a space war.[All Comments] [Add Comment or Rating]
H. G. Muller wrote on 2022-05-26 UTC

It doesn't say how the Bomber moves when it doesn't explode.

Is this game winnable with a reasonable advantage? I am not sure even a Starship could catch a Hideout.

Fergus Duniho wrote on 2022-05-26 UTC

A graphic diagram would be nice. Unfortunately, we don't have any images matching your piece names. So, you may have to draw them yourself. FYI, the usual convention is to use capitals for White's pieces and lowercase for Black's.

Chennis. (Updated!) Kyoto-Shogi-inspired variant (with alternating piece sides), with a tennis theme.[All Comments] [Add Comment or Rating]
Fergus Duniho wrote on 2022-05-26 UTC

Okay, I made a few edits and published this. I checked Small and unchecked Modest, because this is a 7x7 game that does not use the usual equipment.

Parahouse. (Updated!) Shogi + Strong pieces. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
Fergus Duniho wrote on 2022-05-26 UTC

I made some edits to the Rules section, and I deleted the Notes section, because it appeared to be code that wasn't working. I don't like the idea of describing pieces only with Betza notation. While it may be used for people who do know it, English descriptions should also be included for readers, since we can't expect all readers to know Betza notation.

Kamikaze Mortal Shogi. Send your Kamikazes on suicide missions in this Shogi variant. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
Fergus Duniho wrote on 2022-05-26 UTC

It is now ready, and I decided to call it Shogi with Impassable Kings, because this name better indicates that it is Shogi with a slight difference. The other alternatives I mentioned for the usual way of handling impasses in Shogi can also be used with Shogi with similar names that put Shogi first. So,

  • Shogi with Confined Kings
  • Shogi with the Try Rule, or Shogi with Thronemate
  • Shogi with Campmate
  • Shogi with Unopposable Kings

The Game of Nemoroth. For the sake of your sanity, do not read this variant! (8x8, Cells: 64) [All Comments] [Add Comment or Rating]
H. G. Muller wrote on 2022-05-26 UTC

Impressive! So far the complexity of this game even deterred me from reading through the rules.

The way it is described is a bit confusing. Basilisk squares and Ghast squares are not really different types of squares, and what happens there just follows from the proximity of the Basilisk or the Ghast. They do not define additional game state. For ichorous squares, the amount of ichor on a square is part of the game state, however. So there really are many different types of ichorous squares. Since having multiple pieces on the same square is normal procedure in this game, Ichor might as well be considered an additional unmovable and unpushable piece. For over-the-board play I would use stacks of Draughts chips for representing Ichor, and just unstack the topmost on every square at the end of each turn.

A suggestion: wouldn't it be 'cleaner' to consider the go-away move a simultaneous operation, if you abandon the idea of having the moving player specify an order? Just displace all adjacent pieces first, and only then calculate the side effects of each from the new position?

[Edit] While reading back through the comments, I see that Adrian King had already proposed the same, concerning the Go Away.

Azgoroth wrote on 2022-05-26 UTCExcellent ★★★★★

Just over twenty years after the initial publication of this page, the first ever computer implementation of Nemoroth is live, complete with a basic alpha-beta pruning AI. You can play in your browser at this link:

The only thing I haven't implemented is the Go Away push order, which I've been putting off due to how laborious the UI considerations are. As a placeholder, Go Away pushes are clockwise from top.

I originally wrote this implementation in TypeScript, but the AI was too slow and I ported it over to C++ using WebAssembly. I plan on open sourcing it eventually once I have more opportunities to clean up the code. This is one of the most difficult software projects I have ever worked on; I have known about Nemoroth since around 2013 but was not a strong enough of a programmer to pull it off until now.

I found a number of ambiguities in these rules, which I have tried my best to address reasonably on the linked page. Some have been covered in this comments section, some not (for example, if a Wounded Fiend leaves an already ichorated square, does the ichor stack to 11+ plies or max out at 10?).

The AI is surprisingly dangerous. It mobilizes the Ghast immediately and WILL advance it to d4/d5 if you let it, usually costing you the game. I have managed to beat it a few times, but it's tough as nails for how crude the programming is. Beware!

Ralph, if you're out there, thanks for this amazing variant. I tried to email you to get permission to make this but alas, I never heard back.

Kamikaze Mortal Shogi. Send your Kamikazes on suicide missions in this Shogi variant. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
Greg Strong wrote on 2022-05-25 UTC

It would be worth it to apply this in normal Shogi, to create a variant 'Impasseless Shogi'.

I would definitely be interested in testing out this idea.

New Submissions for Review. A listing of all submissions still awaiting editorial approval.[All Comments] [Add Comment or Rating]
Daniel Lee wrote on 2022-05-25 UTC

Hi, still waiting for Chennis (submitted January) to be published

Kamikaze Mortal Shogi. Send your Kamikazes on suicide missions in this Shogi variant. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
Fergus Duniho wrote on 2022-05-25 UTC

It woould be worth it to apply this in normal Shogi, to create a variant 'Impasseless Shogi'.

I was thinking the same thing with the name Impassable Shogi, or perhaps Impassable Kings Shogi to make the meaning more clear.

H. G. Muller wrote on 2022-05-25 UTC

This is an interesting idea. It also would make kings a very large threat to each other, when they get close in ranks. Because they create an artificial board edge against which the opponent could be checkmated. Or could provide protection for a general dropped in front of the enemy king.

It woould be worth it to apply this in normal Shogi, to create a variant 'Impasseless Shogi'.

ArchMage Chess. 10x10 30v30 Fantasy Chess. (10x10, Cells: 100) [All Comments] [Add Comment or Rating]
Jean-Louis Cazaux wrote on 2022-05-25 UTC

Thank you Cyrus for your understanding. Having a theme is good. I wish you success with ArchMage Chess.

Cyrus Arturas wrote on 2022-05-25 UTC

Thank you all for reviewing this rule set and for your constructive criticisms. I have been seriously contemplating the problems you have presented and your suggestions. I really appreciate your help and input as this is my first time inventing a chess variant or posting my ideas on this website. I think that it is important to respect the veteran inventors who came before me and I will do my best to acknowledge their concerns and to correct any mistakes and errors I may have made when creating this rule page.

When it comes to the names of the pieces I have chosen I didn’t realize at the time how others may be bothered that I changed the names of already well established move sets for fairy pieces. I understand that there is a long historical tradition within chess variants to keep the names of familiar fairy pieces and their move sets recognizable as to not cause confusion with other veteran players. My goal when designing ArchMage Chess was to create a chess variant that payed tribute to worlds such as Dungeons & Dragons and the Lord of the Rings universe. I wanted to make a fantasy chess game that had an element of magic implemented into it hence why I created the Mage with the ability to teleport and summon.

After some thought I decided that it would be best to rename these pieces with their more well known names from other variations. I decided that I will call the Jester a Phoenix, I will have the Griffon & Manticore instead of the Dragon & Griffon as they are named now, and the Demon & Demoness will become the Dragon King & Dragon Horse. I will call the Princess an Amazon and the Warrior Prince will become the Lion. I will rename everything besides the Mage, Sorceress, and the ArchMage as these pieces are unique and their rule sets are the focus of what makes this chess variant different from other games. As a Christian myself I understand the controversy surrounding the term “Demon Summoning” and how this would be received poorly in the west. I will change the term to “Dragon Summoning”. I know that even the Dungeons & Dragons theme, fantasy, and magic itself is controversial within the Christian community.

I will be working on adding rules explaining the situations that arise with unit swapping and promotion on the same turn as well as how the en passant rule would be affected by this.

I will consider different solutions to the summoning drop rule because I agree that as it is stated now the rule seems too powerful for actual play even with the 1 turn wait limit. It makes it so there is no great risk or severe punishment enough for losing a summoned piece if you can just easily summon it again later. This would make it so players would not value their summoned piece enough to keep it alive and may abuse it by sending it on suicide missions over and over again in order to gain an advantage. I think you all have presented really good ideas of ways to limit the power of the summoning ability. As it stands right now I like the idea that the captured summoned unit stays in the hand of the capturing player instead of returning to the hand of the original player who summoned it. This would be similar to shogi’s drop rule. The only way the player would be able to summon the captured unit again is if they have a summoner unit still in play. If the original player wanted to summon it again they would have to recapture their original unit.

I will remove diagram images that are considered excessive, repetitive, or explain rules that are already common knowledge in orthodox chess. I will simply state that the game follows the rules of orthodox chess and I will add any rules or problems that are unique to this variation of chess. For the setup description I will add the coordinate points for the starting pieces instead of just simply stating how many pieces a player starts with. I will remove the large bold headers at the beginning of each piece name as well as add a link into the pieces names directing towards the appropriate page explaining the historical fairy piece.

Thank you for taking the time to review this page.

Parahouse. (Updated!) Shogi + Strong pieces. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
Daphne Snowmoon wrote on 2022-05-25 UTC

Can this be published ?

Kamikaze Mortal Shogi. Send your Kamikazes on suicide missions in this Shogi variant. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
Fergus Duniho wrote on 2022-05-24 UTC

One more option is to forbid Kings from occupying the same rank. This could be programmed by giving each King a checking move to every space in its rank. Being unable to occupy the same rank, Kings could not pass each other, and the impasse situation where each King has moved into the opponent's camp would never arise. If one King passed into his opponent's camp, the other King would have to be there too, which would leave that King vulnerable to attack. Additionally, the King in the opponent's camp would be unable to move to the last rank, which would leave it more vulnerable to some attacks.

I like how this option makes the game more decisive without fundamentally overturning gameplay. Unlike some options, it has no effect until the Kings come close together. Also, it's the easiest to program, it doesn't affect the movement of any piece but the King, and it doesn't add any new goals to the game.

Checkmating Applet. Practice your checkmating skill with fairy pieces.[All Comments] [Add Comment or Rating]
Aurelian Florea wrote on 2022-05-23 UTC

Thanks once again for the insight!

H. G. Muller wrote on 2022-05-23 UTC

There is one caveat: R2 (and WD) lose their mating potential on 12x12. Adding Camel moves cures this, even up to 16x16 (the largest the Applet can do). So I have little doubt R2-then-B would have mating potential there.

For B2-then-R very large boards actually make it easier. Because from a large distance you could use the R legs as if the piece were a Rook. Even an invulnerable one, because the bare King cannot approach it. And the F step can be used to tighten the noose around the bare King. So it should be a very easy checkmate.

Kamikaze Mortal Shogi. Send your Kamikazes on suicide missions in this Shogi variant. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
H. G. Muller wrote on 2022-05-23 UTC

My guess is that forbidding kings to face each other would not help. Exposed kings get checkmated very quickly in Shogi. So when the manage to cross it is always surrounded by a group of friendly pieces, from which they are chased out, and then again get new pieces dropped around the to survive.

I could imagine that the Kamikazes present the same problem as Pawns, when you are allowed to drop more than one of those in the same file.

Fergus Duniho wrote on 2022-05-22 UTC

Ever since I played a game with Greg that ended in an impasse, I felt this game may be too drawish, and I've sometimes considered changing the rules to fix this. The rule change I was thinking of was to forbid Kings from crossing to the other side of the board and to give them the ability to check each other from a distance, as in Eurasian Chess. However, it has come up that Shogi has its own rule for handling impasses, and there are alternatives to it.

The rule in Shogi is if each King has moved to the opponent's camp, which is the ranks the opponent's pieces start on, players may agree that an impasse has been reached and count pieces to determine the winner. Kings count for nothing, Rook and Bishops, promoted or not, each count 5, and other pieces each count 1. A player with less than 24 points loses. Because of the piece attrition in Kamikaze Mortal Shogi, it is possible that each side would have less than 24 points. So, instead, it could be played with the rule that whoever has more points wins. But I don't like this counting solution, and others don't too.

An alternative rule proposed for Shogi is called the Try rule. This involves winning by moving one's own King to the space the opponent's King began on. I don't know if this involves moving there only if it is safe or if it becomes a condition only after both Kings have crossed into the enemy camp. I would propose making it a winning condition only if both Kings have crossed into the opponent's camp and it moves there safely.

Similar to this is the Campmate rule, which allows a player to win by reaching the last rank with his King. I would propose the same conditions on it that I am proposing for the Try rule.

Another possibility for dealing with impasse is to reverse the directions that the opponent's pieces may move when the King moves into the opponent's camp. Additionally, pieces could be allowed to treat their own camp as a promotion zone when the opponent's King is there. These changes would discourage players from moving their Kings to the other side of the board without strictly forbidding it.

One more possibility is to allow Kings to check each other from a distance but to not forbid Kings from crossing to the other side. Instead, the ability of Kings to check each other from a distance would usually prevent both Kings from crossing to the other side, and if they happened to do so by having another piece between them on the same rank, this ability would provide an incentive for leaving the King more exposed.

Checkmating Applet (3 vs 1). Practice your checkmating skill with fairy pieces.[All Comments] [Add Comment or Rating]
H. G. Muller wrote on 2022-05-22 UTC

Good catch. This problem surfaced everywhere after a change in the general Diagram script. I did fix it in most places, but apparently forgot to fix it here. It should work now.

(The reason was that this applet abuses the routine WeirdPromotion, which would be called for every move, to invoke the routine that fetches the best move from the end-game table and play it. But at some point the Diagram script started to call WeirdPromotion twice, also once to figure out whether it should allow the user to choose a piece. This to also support unexpected promotions that involve a choice. So the WeirdPromotion routine included in this applet should be more careful now, and only invoke the routine for playing a move when it has not already been done.)

Parahouse. (Updated!) Shogi + Strong pieces. (9x9, Cells: 81) [All Comments] [Add Comment or Rating]
Fergus Duniho wrote on 2022-05-22 UTC

I see Campmate was mentioned in the comments to that video 5 months ago.

Checkmating Applet. Practice your checkmating skill with fairy pieces.[All Comments] [Add Comment or Rating]
Aurelian Florea wrote on 2022-05-22 UTC

Thanks for the analysis!

Checkmating Applet (3 vs 1). Practice your checkmating skill with fairy pieces.[All Comments] [Add Comment or Rating]
Aurelian Florea wrote on 2022-05-22 UTC

I see another problem. The computer moves twice!

25 comments displayed

Later Reverse Order EarlierEarliest

Permalink to the exact comments currently displayed.