This variant has some funny rules that required special attention. One was promotion: not only Pawns promote, but a Prince reaching last rank can optionally promote to Queen too. And a Ship can promote to Griffon in the last-rank corners. This was handled by defining Prince as first piece, and specifying only one promoting piece, with as only choices Prince and Queen. This invokes the normal promotion procedure for Princes, letting the user select from the legend table.

Pawn and Ship make use of the user-supplied JavaScript function WeirdPromotion. This automatically promotes these pieces when they reach their respective zones, as in this cases there is no promotion choice.

Another unusual feature of this variant is that, when checkmated, Kings can swapped with Princes,wherever these are located. To make the diagram indicate this possibility, the King was equipped with a universal-leaper move U. The modality 'x', which was already introduced on non-final legs of multi-leg moves to indicate relaying of powers, is now used for indicating such a piece swap with a friendly piece on final (or only) legs.

Adding a plain xU to the King moves would allow it to be swapped with any friendly piece, however. To single out the Princes, we declared the board to be zonal by providing a JavaScript function BadZone. This function tests the the target location for containing a piece of the same color as the mover, and declares the to-square invalid if a non-Prince if found.

There's a problem with the King swapping move. It just gets rid of the Prince instead of switching with it.

If you're into quirky variants, you'll love this one. Just get a load of the ship piece type, for instance.

Is the King permitted to switch places with a Queen or only with an unpromoted Prince?

A very old variant of mine. King can switch only with Prince, so unpromoted, not with Queen. So the player has to decide if he promotes his Prince or not.

I was looking to this Interactive Diagram (thanks HG). The Prince's move is not correct. It is not K. It should be KimfnD.

I was looking to this Interactive Diagram (thanks HG). The Prince's move is not correct. It is not K. It should be KimfnD.

The description in the page says K, so that is what I use in the Diagram.

Exact HG, I had not realized that. This is the consequence of the fact that I can't edit this page like I do with my other games. (I have the same problem with Shako).

This page on our site is not updated. The updated page is here http://history.chess.free.fr/tamerlane2.htm

If I could I would update the page on CVP too. I could then explain why this evolution.

OK, I see. But the Diagram is intended as a means for practicing the variant that people have just read the rules of in the article, so I think it would be bad to surprise them with other rules. If you manage to correct the article, I will adapt the Diagram accordingly. Of course it would be better if you included the Diagram in the main page of the article; then it will not be pushed into oblivion by later discussions like this one. And then you can correct the Prince move yourself.

Yes indeed, if I update this page I wish to keep the diagram too, it's very nice to have it. Thanks

The King's Succession rule is now also supported by the AI of the Interactive Diagram: a new parameter 'succession' can be used to specify which piece type can swap with the King in case the latter has no other legal move to escape check. The easiest way to see this in action is to set up a position where checkmate can be delivered (e.g. move a white Pawn to c4 and Prince to c5, the black King to a5), switch on the AI, and deliver the 'checkmate' (Prince c5-b5). The AI will then swap the King with one of his Princes.

Although I am the author of this page, as it is an old one I have no possibility to edit it. May I be given the right to do so by Fergus or an editor? Thanks a lot.

You can if you become an editor, as it will require SCP or SFTP access to the site. Since you are one of the earliest editors for this site and a published author on Chess variants, I have no objection to reinstating you as an editor if you so wish.

It will be a pleasure if it could help but I'm afraid it won't. The reason is that all editors here are experts and skilled in computer science. Often, I don't even understand what you are talking about. To start with SCP or SFTP are completely unknown to me.

To come back to my question, we had the same discussion sometimes ago for Shako (see the comments at this page). Ben Reiniger helped for that. You were speaking of a "migration" then. It would be nice if authors of ancient pages could edit their pages without passing by the step of being editors of the CVP.

Thanks

all editors here are experts and skilled in computer science.

You are an expert in Chess variants, and not all editors are skilled in computer science. As the webmaster, I have to know my way around computers, but when it comes to editing pages, that doesn't require any computer skills.

To start with SCP or SFTP are completely unknown to me.

SCP and SFTP are just modern alternatives to FTP, which you must have been using when you were an editor before. SCP stands for Secure Copy Protocol, and SFTP stands for Secure File Transfer Protocol. Each works the same way as FTP and just requires you to use a program that supports it.