Spirits of the Knight

by Peter Fayers
From Variant Chess, Volume 3, Issue 23, Spring 1997, pages 57-59.

I have recently become fascinated by Augsburg Chess, more so than any other fairy form. The ability of normal units to gain and lose powers appeals to me no end.

However, I soon ran out of inspiration; there seems to be a limited number of ‘special effects’ that can be demonstrated with Augsburg even allowing for the differences between Pawn-Augsburg and Piece-Augsburg — thank you, Variant Chess! So I stretched my imagination further and invented a new fairy form, which I call ‘Spirits of the Knight’ (a catchy title, but a bit long, so we will abbreviate it to S-Spirits). This (I think) is virgin territory for exploring effects of units gaining or losing extra powers.

1. When a knight is captured, its spirit lives on, joining the captor and endowing it with the power to move as a knight in addition to its normal movement.

(A/B/A') P. FAYERS

Spirits of the Knight
Helpmate in 3/ 3/ 2½

Looking at problem A, this solves by 1 Sc2 Ka4; 2 Ka1 Kb3; 3 a2 K×c2‡. The white king, having captured the knight, is now inspired (i.e. it hosts the spirit), checking and thus mating the black king.

Well, nothing new there; this idea is the basis of Absorption Chess, and can be traced back centuries to Radha-Madhava (a variant of Indian Chess, according to the ECV p.152).

However, I did mention that units can also lose these extra powers, and so we have:

2. S-Spirits are flighty, and will immediately leap to another unit if its host moves to a square an S-leap away from that unit.

In problem B, after 1 Kf5 R×d7, the rook is inspired. Now; 2 Kg4 Rf6, the rook has moved to an S-move from the black king, so the spirit transfers, allowing 3 Kh2 Rf2‡. Yes, mate, as (e.g.) on 4 Kg1?? the spirit would leap to the wK, allowing K×K!

A word on terminology. We use the dollar sign for the spirit: placed after the move, it means that the unit has acquired the spirit; placed in the middle of the move, it means that the spirit has transferred to another piece, and at the front of the move it means that the spirit has remained with its host during the move. With this terminology (suggested by RT, and a vast improvement on what I had been using in the first draft), the solution to B would be written: 1 Kf5 R×d7\$; 2 Kg4 Rf6\$g4; 3 \$Kh2 Rf2‡

At this stage we need to clarify what happens when there is a choice of units to which the spirit may leap; the answer is simple: Nothing.

3. Where there are two or more units a knight-leap away from where the S-Spirit ends its move, it doesn't transfer; it remains with its current host.

(C) P. FAYERS

Spirits of the Knight
Serieshelpmate in 7

In problem C, after 1 B×d6 black may not then play 2 \$Bf5?? Faced with a choice of Pe7 and Kg7 to move to, the S-Spirit would stay with Bf5, checking the white K, illegal in the middle of series-play.

This problem involves one of the reasons I like Augsburg, the ability to change the parity of bishops. In this problem all three bishops change colour, allowing a smothered mate of the black king on a1. With that rather broad hint, try it yourself!

Now things start to get complicated. I feel that what we have is too restrictive; an S-Spirit will only move when its current owner wants it to. So I developed a rule that enables the opposition to entice it away.

4. A Spirit will also leap to any unit that ends its move a knight's move away.

(Note, that although I mentioned ‘the opposition’ in regards to this rule, this is not restrictive. S-Spirits are totally impartial, and under both rule 2 and rule 4 will transfer its allegiance to either a friendly or an enemy unit without fear or favour).

As an example, problem A' is formed from problem A (which is invalid under the modified rules) by making the Sa1 white, and changing the stipulation to H‡2½ (for convenience of printing we also transfer it to the h-file.) With white to move first: 1 ... Kg4; 2 K×h1\$ Kf3; 3 h2 Kf2\$‡. On moving to f2, the white king attracts the spirit, which transfers its allegiance. (This dictates the wK path: 2 ... Kg3? would lure the spirit away prematurely.)

(D) P. FAYERS

Spirits of the Knight
Helpmate in 3

As implied in the examples, by ‘unit’ we include Kings and Pawns — any unit can host a Spirit of the Knight. You should be able to solve problem D in seconds, except perhaps for working out which of white`s plausible mating moves actually does, and why the other doesn’t.

This really is all there is to it. I know that the rules are extensive, but hopefully S-Spirits will provide a fruitful new source of fairy problems. Here are some more examples.

(E) P. FAYERS

Spirits of the Knight
Reflexmate in 3

In the reflexmate E, the wK and black pawns are locked solid — we have to engineer for the bK to be able to deliver mate. We start with the brutal key 1 Sc6†, forcing 1 ... Kd5, after which 2 Sd6 leaves both knights en prise, and black has no option but to take one of them.

F was provided by your problem editor. (This should be obvious from the diagram. As his VC129 conjures up an en-passant capture without any black pawns on the board, and likewise in VC152, the complete dearth of rooks in the diagram means that the solution naturally involves castling, it seems almost inevitable that a ‘Spirits of the Knight’ problem from Ronald wouldn`t have any mundane features like knights in it!)

(F) R. TURNBULL

S-Spirits, Helpmate in 2

So, this problem involves some retroanalysis. Purists may point out that, in strict retro terms, there must always be a total of four (knights plus S-Spirits) on the board at any one time. I agree. I acknowledge that these rules are incomplete. What happens when a host with an S-Spirit familiar is captured? Can a host have more than one familiar at a time? And so on, and so on. I haven`t tried to resolve these questions because I haven`t needed to. As and when anybody wants to use one of these situations to show some special effect, they are quite at liberty to decide for themselves what happens, thereby setting the standard for other composers in the future.

(G) P. FAYERS

Spirits of the Knight
Camelrider a2Mate in 2

In the meantime, problem G shows a new slant on an old theme, and again demonstrates that the possession of an S-Spirit familiar can restrict, as well as enhance, mobility. Sorry about the Camelrider; I wanted to set this with the traditional Rook-Bishop Nowotny effect, but in order to avoid the W Bishop being able to block the bR line, I either had to use a grid, or a 12×12 board with a Nightrider as the key piece. The setting with the Camelrider seemed the cleanest of the three possibilities.

Did I just say ‘Nightrider’? OK, as a final little demonstration, I have decided that nightriders have spirits too. Problem H shows one weird effect of this — a long-range smothered mate by a lone King! (More an exercise than a problem. I am not really into nightriders. Specialists in this field are invited to demonstrate the efficacy of their spirits.)

(H) P. FAYERS

Nightrider b8
N-Spirits, Helpmate in 3

I`ll probably decide that camels and zebras (and their riders) have spirits as well. — When I need to.

Ronald reminds me that this journal is read by people who actually play variant games, as well as problemists, and so as a service to them I will try to fill in the holes I mentioned, in order to end up with a playable game you can try out. I would suggest:

5. When an inspired unit is captured, the spirit remains, transferring its allegiance to the captor.

6. The astral plane over the chessboard only contains enough ethereal energy to support one spirit.

When a second knight is captured, the first spirit is released from the purgatory of the chessboard (a phrase used with considerable feeling), and goes to its Valhalla. (This gives an interesting possibility: a player can get out of check by capturing a knight elsewhere on the board!)

I believe that these two extra rules are all that is needed to make the variant playable, and a neat consequence is that, once a knight is captured, there will always be one (and only one) spirit on the board, making it fairly easy to keep track of. I look forward to seeing some game scores!

(I) R. TURNBULL

S-Spirits
Helpstalemate in 2
Partial Retro-Analysis

With these last rules in mind, I leave you with problem I, another offering from your problem editor; a helpstalemate.

With thanks to Cedric Lytton, for his encouragement, help, and unparalleled (in a human, at least) cook-finding ability.

Solutions