Chess Piece Essay: Other concepts

This one here's for the concepts that aren't covered by the previous essays, which are more concerned with movement.

Take it or Leave it

Capture is taken for granted in chess. Capture by replacement is assumed in so many chess variants that it is to be noted whenever a capture doesn't simply involve moving to an enemy piece and taking it, e.g. en passant, Chinese chess cannon. Variant methods of capture are better covered on its own article but it's worth nothing how Ultima is the game that has opened this hitherto unexplored area in chess variants. While not every capture thought up by Robert Abbott has gotten much attention, the mechanics brought up by this game and other inspirations is still open for exploring.

Ultima itself is a worthy first try at pitting capture dynamics against one another, though it has its flaws. The game itself can be described more as a chess-type game with pieces of different powers. Rococo is a great game derived from this idea, keeping some pieces while replacing some with new ones, leading to more piece variety.

Some games have been made based on a change in capture mechanic. An old variation is Rifle Chess, where captures are done but the capturing pieces do not move. Dynamo chess pieces push and pull other pieces instead of simply displacing them, with removal done by pushing pieces off the board. Jumping chess takes pieces by, indeed, jumping on them like checkers. Each of these games have differing dynamics thanks to this change in capture.

All Hail the Piece, Baby

It's not chess without check or checkmate. Most chess variants have a piece that must be protected at all costs. If a piece cannot be allowed to be captured ay any cost, it is said to be royal. In practice, the royal piece is not actually captured, but if it's threatened to be captured next turn, then the piece and player are in check and must get himself out of check on his turn.

In orthodox chess, the royal piece is the king, and there are rules that center over making sure the king doesn't die, mostly involving making sure a move that captures the king doesn't happen. 

The original goal is of course to capture the king, the concepts of check and checkmate stemming from the importance of this goal slowly making the actual act of capture a formality. This paradigm shift has made consequences in legalities that wouldn't exist if one could just simply take the king and end it there. One of them being checkless chess, a simple stipulation with interesting implications.

More legalities abound with stuff like stalemate. Originally a win based on the goal of capturing the king, in modern chess stalemate is a draw thanks to it being a state of being unable to move legally instead of the king being directly threatened. Stipulations between variants vary but are more of a legal requirement; the area where checkmate and stalemate positions matter more is chess composition.

The orthodox chess king moves as a leaper, rather agile for a piece whose preservation is a must (e.g. king geometries in pawn endgames). A more agile piece is any rider, which has given rise to the idea of not letting agile riders move past a square that would put it in check if stopped to make catching them easier. Speaking of riders, it is still an open question if a pinned piece can make a null move that requires it to move anyway.

Quick notes of interest: the anti-king, who is checked if it is not within capturing range; and the contramatic king can move into checked but cannot be checked (in contramatic chess a player unable to do any move other than a check loses). King variations that would only exist as offshoots of the current concept of royalty.

Multiple royal pieces have their own quagmires: What happens when one is checkmated and the other isn't? If both pieces are checked at the same time does that suffice as a win?

Some chess variants do not have a royalty stipulation, such as in Losing Chess or Mock Chess. In these games, the goal is to lose your pieces or capture all your enemy's pieces respectively. How much this deviates from chess is something worth discussing, though it has led to asking if checkers can be classified as a chess variant.

Extinction Chess has a distinct property of all pieces technically having royalty, as the goal is to eliminate every piece of a type. I'm bringing up this game as a borderline example of how royalty works in chess.

A Bit of Reincarnation

Pieces do not return when captured in most variants, a given in most cases. Returning captured pieces developed in Japan through the drop mechanic, the most common form of return mechanism. Parachuting pieces opens up new tactical ideas and is just a fun idea to play with all around.

Within chess composition circles is another way of returning pieces by returning captured pieces back to set squares. Circe chess has gone beyond its original form in 1968 and tons of Circe in various shapes and sizes abound.

These two mechanisms each deserve a piece on their own so I will close this article by noting that Circe is only here rather loosely, most rulesets still allow full capture and in a way the return of the piece onto the board immediately makes it questionable if the capture is a real capture at all.