I love Chess variants. The origin of this love is twofold. First, I adored the idea of “Martian Chess,” or Jetan, that Edgar Rice Burroughs in The Chessmen of Mars, complete with full rules of the game. Second, my father loved classic boardgames, including chess and chess variants. As a child he taught me Go, Checkers, Chess, and then Shogi and Xiangqi. When I fell in love with Jetan we played it for months (using tape to temporarily turn a Go board into a Jetan board), and he introduced me to Chancellor Chess, Checker-Chess, and a tone of other variants.

When Dragon Magazine published Dragon Chess, he and I used out multiple chess sets and many of my lead miniatures to make a set, and played. I don’t think we ever got through a whole game, but we made multiple runs at it.

(Somewhere in here I also found the video game Archon, which was also a big influence).

So, I’ve adored the idea of chesslike games for a long time, and have played Knightmare Chess, and various 3-, 4-, 5-, and 6-player chess variants. Eldritch Chess is an outgrowth of that old passion, and while this version is highly experimental, it’s grown enough I want to have all the current rules in one place.

Also, a BIG shoutout to Mike Myler, who first collated a lot of my social media posts into a pdf, and codified some rules I had hinted at but not written down. Thanks, Mike!

Basic Rules
Eldritch Chess uses the rules of regular chess, with the possible addition of new special pieces called “eldritch pieces.” Each player begins before play with a typical chess army of eight pawns, two rooks, two knights, two bishops, a queen, and a king, but may substitute a number of pieces for eldritch pieces.

Setup and Substitution

All eldritch piece substitutions are decided on prior to pieces being placed on the board. Then, after both sides have decided and noted down what pieces they are using, each side places all their non-eldritch pieces on the board, each in one of its legal starting places, alternating with White placing the first piece. If one side has more non-eldritch pieces, they place all their remaining non-eldritch pieces after the two sides stop alternating.

Then, the two sides take turns placing their eldritch pieces using the same rules as for non-eldritch pieces, above. When placing an eldritch pieces, a player must put in on the beginning square of one of the pieces it replaces, if possible. If not possible, the player chooses any open starting square on the first 2 rows of their side of the board. If there are no such open squares, the eldritch pieces is placed on their third row, as close to the side of the board as possible.

Each time an eldritch piece is placed, which piece it is and what piece(s) it is replacing is revealed to the opposing player.

First Game

It’s recommended that when first playing Eldritch Chess that each player be limited to a single
eldritch piece, increasing the number of allowed eldritch pieces by one for every three matches played.

Matched Sides

To ensure balanced sides, it is possible for eldritch chess to be played with both sideshaving the same eldritch pieces. The players decide on how many substitutions they will have, limiting themselves to an even number (2 eldritch pieces, or 4, 6, or 8). Black then selects one eldritch piece both sides will begin with, and which piece(s) it replaces. White then selects the next eldritch piece and what it replaces, and the players continuing taking alternating turns until all eldritch pieces are selected. Players then set up their pieces, as described in Setup and Selection, above.

Invoke

Some pieces have an invoke. this is something the piece does when you invoke it, which can only be done on your turn and counts as your move, but does not move the piece using its normal movement.

Promotion

Pawns retain the ability to promote if they reach the far row, but can only promote to standard chess pieces (even if you did not being with any of that piece on the board), and eldritch pieces you began the game having on the board. Other pieces only promote if they say so, and may have special rules. A peice can never promote to a liege.

Piece Types

An Eldritch Chess, some pieces are defined as spells, priests, royals, or lieges. Of the standard chess pieces bishops are priests, kings and queens are royals, and the king is a liege. Some eldritch pieces have special rules that interact with these types. Each player must have one and only one liege, which can castle as a king (unless it states otherwise), and is subject to the rules of check and checkmate as a king.

Victory Conditions

Normal victory conditions are to checkmate your opponent’s liege. If a liege is in check, its player must take it out of check. A liege cannot choose to enter check. In some cases, destroying your opponent’s liege may occur without it ever being in check, such as if it is destroyed by a Fireball. This is considered checkmate for victory conditions.

If neither side has pieces remaining capable to checking the opposing liege, the game is a draw. For example, if both players are down to an archmage and some oozes, the game is a draw.

Eldritch Piece Rules

Abjurer
An Abjurer can move and capture 1 space in any direction. An Abjurer cannot be captured except by royal pieces, and cannot be jumped over (even by pieces that normally can jump). Substitution: You can replace one or both rooks with abjurers.

Archmage
The Archmage can move up to 2 spaces in any direction, jumping. It cannot capture. It cannot castle. It is a liege. Substitution: The Archmage replaces your king.

Barricade
The Barricade moves/captures 1, 2, or 3 spaces orthogonally or vertically. It can invoke to Block, preventing the opponent on their next move from capturing it, moving pieces adjacent to it, or jumping over it. It is a spell. You can replace one or both rooks with Barricades.

Berserker
A Berserker moves and captures as a pawn. It can move and capture as a knight or queen, but after doing so it is removed from play. The Berserker cannot check a liege. It can promote on the back row as a pawn. Substitution: You can replace one or both rooks, and/or one or both knights, with bersekers.

Celestial
A Celestial moves and captures up to 4 diagonal spaces. It can jump pieces. It is a priest. When the Celestial is captured, you can immediately promote one pawn that is not in a position to capture or check if it becomes a knight into a knight. Substitution: You can replace your queen, and/or both bishops, with one Celestial.

Conjurer
A Conjurer moves and captures like a pawn. If you have fewer than 8 pawns, as an invoke the Conjurer can create a pawn you control as a move, placing it in a clear adjacent square. Substitution: You can replace your queen, and/or both rooks, with one Conjurer. You cannot have more than one Conjurer.

Court Magician
A Court Magician moves as a king or knight, and promotes as a pawn. It is royal, and remains royal after promoting. You can replace one or both rooks, or both knights, or your queen with one Court Magician.

Diviner
A Diviner moves and captures as a king. You can discard a Diviner without taking a move to force your opponent to undo the move they just took. It’s still their move, but they cannot repeat the same move.
Substitution: You replace your queen, and/or both bishops, with one diviner.

Geomancer
The geomancer moves and captures as the king, but is not a liege. As an invoke, the geomancer can add a strip of four squares to a side of the gameboard. All the edges of one long 4-square side must be adjacent to the original board, and black and white squares alternate with the original board. The added squares can be moved on as normal, but don’t change where pieces promote. Substitution: You replace one or both knights with geomancers.

Ghost
The Ghost can move 2 spaces in any direction. It does not capture pieces, but instead suborns them,
sharing their space and moving with them and preventing your opponent from moving them. It
cannot suborn priests. While suborning, the Ghost moves as itself or the suborned piece, whichever you select for each move. If captured while suborning a piece, the Ghost is destroyed and you place the suborned piece in an adjacent open square where it is returned to your opponent’s control. Substitution: You can replace your queen, and/or both bishops, with one Ghost.

Doppelganger
A Doppelganger moves, captures, castles, and follows the rules of check and checkmate as your king. It is not a liege or royal. However, both your king and Doppleganger must be checkmated for you to lose the game. Substitution: You can replace your queen, or both knights, with a Doppleganger, but may only have
one Doppelganger.

Dragon
A Dragon can move 2 spaces diagonally or orthogonally, and can jump over a piece. It can capture a piece it lands on, or one in any square adjacent to where it lands. Substitution: You can replace both knights with Dragons (but not just one).

Druid
The Druid moves and captures as a pawn. If it doesn’t already have one, it can create a beast as a move. A
beast appears in an unoccupied adjacent space, and moves and captures as a knight. A beast can only move twice, then disappears. If a beast is captured, so is its Druid. The Druid is a priest, but its beast is not. Substitution: You can replace your queen, or both bishops, or one bishop and four pawns, with druids.

Enchanter
An Enchanter can move 2 (and only 2) spaces diagonally or orthogonally. It can capture only by moving into an adjacent enemy piece. An enemy piece adjacent to an Enchanter can’t move. Substitution: You can replace a queen, or a pawn plus one bishop, knight, or rook, with an enchanter.

Evoker
The Evoker moves and captures as a pawn. It can also invoke to capture a piece that is 1 vertical and 2 orthogonal spaces away, or 2 vertical and 1 orthogonal spaces away without moving. The Evoker can capture your own pieces. Substitution: You may replace one or both rooks with Evokers, and/or your queen, and/or one or both knights, but cannot have more than three total Evokers.

Familiar
The Familiar moves/captures 1 in any direction. As an invoke, it can hop onto an adjacent piece of yours. It thereafter moves and is captured with that piece, until it uses it invokes again to leave the shared space and land in an adjacent, unoccupied square. You can replace one or both bishops with Familiars.

Fiend
The Fiend moves up to 3 spaces in any direction, can jump pieces, can turn once during its movement, and can capture friendly pieces. The fiend can capture but not land adjacent to a priest, and the fiend captures a friendly pawn when landing next to it. Substitution: You can replace one or both knights
with fiends.

Fireball
The Fireball moves/captures 1, 2, or 3 spaces diagonally. When it captures a piece that piece, the Fireball, and every adjacent piece, is destroyed. If a liege is destroyed, this is treated as checkmate. It is a spell. You can replace one or both rooks with Fireballs.

Gargoyle
The Gargoyle moves as a knight, but cannot jump pieces. It cannot be captured, removed from the board, or suborned by spells. You can replace one or both knights and/or one (but not both) rook and/or one (but not both) bishop with Gargoyles.

Giant
The Giant moves and captures 1 or 2 spaces orthogonally. As an invoke, it can throw any adjacent non-royal piece of yours 2 or 3 spaces in any direction, jumping pieces, to an unoccupied space. You can replace one or both rooks with Giants.

Gremlin
A Gremlin moves and captures as a pawn, but does not get a double move on it first turn, and does not promote. If it reaches the far row, it turns around (moving and capturing toward you, rather than away from you). You can replace one or both knights or bishops with three gremlins each, or a rook for 5 gremlins, or a queen for 9 Gremlins. However, you cannot have more than 24 total pieces at start of the game when using Gremlins.

Highlander
The Highlander moves and captures as a queen. When captured, it returns as a bishop or rook (your
choice) on your next turn, on any unoccupied square on your back row, without requiring a move to do so. (If you do not have an unoccupied square on your back row, it can appear on any unoccupied square on the first row closest to you that does have one.) If captured again, it returns as a knight, and if again as a pawn. Substitution: You can replace your queen and one knight and one pawn, with one Highlander.

Illusionist
The Illusionist moves as a bishop, rook, knight, or pawn, but only captures as a pawn. Substitution: You can replace your queen, or one rook, with an illusionist. You do this by noting which piece you swapped one of those pieces for an illusionist, but don’t have to reveal to your opponent which it is until the Illusionist is first moved. When placing pieces, you don’t place any queen or rook until you place your illusionist, at which point you place the Illusionist and all remaining rooks and queens.

Initiate
The Initiate can move 1 forward or 1 to either side, but can only capture when moving 1 forward. It can
be promoted to any priest if it reaches the back row. The initiate is a priest. Substitution: You can replace up to two pawns with initiates, or as many as you like if you also sacrifice a knight.

Lightning Bolt
The Lightning Bolt moves as a pawn (with all associated rules), but can take two moves (including capturing twice) as your turn. It is a spell. If it promotes to a knight, it retains double moves and is still a spell. You can replace your queen and/or a single rook for a Lightning Bolt.

Miasma
Miasma can move one space orthogonally, but cannot capture. As an invoke, it can destroy all non-royal pieces in squares adjacent to it, including you own. It is a spell. You can replace one or both knights with miasmas.

Mystic
The Mystic moves and captures as a pawn. If captured, the Mystic can be immediately return to its starting space without taking a turn. It captures any piece in that space. Substitution: You can replace one or both knights, and/or one of both rooks, with Mystics.

Necromancer
The Necromancer moves as the bishop. As an invoke, a piece captured by the necromancer can be used to replace your identical missing piece, placing it in the starting position of the piece being
replaced. The Necromancer does not block the movement of enemy pieces. Substitution: You may
replace one bishop and a rook, and/or one knight and a rook, and/or your queen, with one Necromancer.

Ooze
An Ooze moves 1 in any direction. It cannot capture or be captured. Your own pieces can always jump
over your ooze. Substitution: You can replace both rooks, or both knights, or four pawns, with two oozes. You can have up to 6 oozes.

Pendulum
The pendulum can move and capture one vertical space forward or backwards. You can replace two pawns with three pendulums, but you cannot have pendulums that bring you over 24 total pieces.

Pontiff
The Pontiff can move and capture 2 spaces along any diagonal. It is a noble, priest, and liege. If you have a pontiff, pawns that reach either of the far 2 rows can be promoted to bishops, but never queens.
Substitution: The pontiff replaces your king.

Portalkeeper
The Portalkeeper has no move and it cannot capture. It can invoke to Portal, switching places with any other piece of yours. A king cannot portal out of check. A piece that is Portaled to a place where it would normally promote does not promote (but can later promote if it takes a normal move that would promote it). You can replace one or both knights with Portalkeepers.

Shadowmancer
The Shadowmancer moves and captures as the king. Your king cannot be put in check as long as your Shadowmancer is in play. You can replace you queen, and one bishop, knight, or rook with a single Shadowmancer.

Shapeshiffter
A Shapeshifter can invoke to become a pawn, rook, bishop, or knight without changing squares. Substitution: You can replace your queen, or any two pieces made up from bishops, rooks, and
knights, with shapeshifters.

Shieldmaiden
A Shieldmaiden moves and captures as a queen. When your liege is in check, you can invoke your Shieldmaiden to swap its position with your liege, if this gets your liege out of check. You can replace your queen and a rook, or a rook, knight, bishop, and pawn, with one shieldmaiden.

Sphinx
The sphinx moves, jumps, and captures as a knight or a pawn. If it does not currently have one, as an invoke it can create a riddle in any empty adjacent sqaure. A riddle does not move or capture, but otherwise acts as a piece for purposes of other pieces’ movement (stopping the movement of any piece that cannot jump, and being captured when another piece ands in its square). Your own priests can capture your riddle, but not other pieces of yours. A sphinx is a priest and a royal. A riddle is a spell. You can replace one knight and one bishop with one sphinx, or both knights, both bishops, and two pawns with two sphinxes.

Valkyrie
The Valkyrie moves and captures as the knight. As an invoke, the Valkyrie can take a pawn of yours (or any piece you have that can be substituted for a single pawn) and return it to play in an unoccupied square adjacent to the Valkyrie. The Valkyrie is a royal and priest. You can substitute your queen, or both knights and one bishop, for a Valkyrie.

Vampire
The Vampire moves and captures as a knight. Each time it captures, it gains the ability to alternatively
move 1 in a single direction of your choice (such as 1 forward, or 1 diagonally back left). If it captures 8
times, it can also move as a queen. It is a royal and liege. Substitution: The Vampire replaces your king, and queen, and any one of your bishops, rooks, or knights.

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