Sunyata Chess

Andernach Chess is perhaps the only chess variant I keep coming back to, again and again, in an attempt to make it playable. I'm absolutely in love with the color-flipping capture mechanic (which, by the way, heavily influenced my Werewolf Checkers), but the inherent drawishness of Andernach Chess - so obvious and easily achievable - has always been its fatal flaw, effectively killing the game as a competitive concept. 
For me, this kind of challenge has always been like a puzzle - one that was an absolute joy to solve.
You remember how I once proposed Neo-Andernach Chess? That was a breakthrough - it finally made the game playable. And yet... something was missing...like a feather’s touch missing from a perfectly balanced blade. 
And now, it feels like everything has clicked into place - the balance, the depth, the sheer elegance of play. No more forced draws, no more lingering "what ifs." Just pure, fluid strategy where every capture tells a story, and victory can bloom from either total control or total surrender.
This... this is the Sunyata Chess I always dreamed of.
While this game shares traits with Andernach Chess, the differences are profound and deliberate.

Sunyata Chess
"Behold this world as empty. Having shattered the illusion of self, you transcend even death. The Lord of Death cannot see one who gazes thus."
— Buddha Śākyamuni (Sutta Nipata)

"Sunyata" (Sanskrit: śūnyatā) — the Buddhist concept of "emptiness," where no independent "self" exists, only interconnected processes.

In this chess variant, pieces change color, shedding their "own" nature - they literally cease to be distinct entities, mirroring Sunyata's dissolution of fixed identity.

Rules of Sunyata Chess
All standard chess rules apply, except as modified below.

Capturing Rules
Color Inversion on Capture:
When a piece (except the king) captures another, it changes color to match the captured piece.
Example: A white bishop capturing a black knight becomes a black bishop.
King Exception:
The king does not change color after capturing if it still has allied pieces of its original color.
If the king is the last remaining piece of its color, it does change color upon capturing (like other pieces).
Illegal Moves:
A player cannot make a move that leaves their own king in check (such a move is illegal and must be retracted).

Pawn Promotion
Standard Promotion:
When a pawn reaches the 1st rank (Black) or 8th rank (White) by a non-capturing move:
- It transforms into a queen, rook, bishop, or knight of its current color.
- The new piece follows normal capture rules (changes color if it later captures an enemy piece).
Promotion by Capture:
If a pawn reaches the promotion rank by capturing:
- No immediate color change - the pawn does not invert its color after capturing.
- It promotes to a queen, rook, bishop, or knight of its original color.
- The new piece can change color only if it later captures another piece (per standard rules).

Move Progression (Progressive Chess)
Turns alternate in the sequence: 1-2-3-4-5…
White: 1 move → Black: 2 moves → White: 3 moves → etc.
The number of moves allowed for any given turn, is dependent on the turn number.
Check Rules:
A check may be delivered on any move of a series. The series then ends immediately—no further moves are permitted that turn.
The checked player must escape check on their first move of the next turn (if impossible, it’s checkmate).
En Passant: Must be executed on the first move of a series, if applicable.

Winning Conditions
Sunyata (Void State):
A player wins the game when no pieces of their original color (including their king) remain on the board.
If only the king remains, capturing according to standard chess rules flips its color → the king 'dissolves into Sunyata' (joins the opponent’s side).
Classical Checkmate:
A player unable to escape check on the first move of their series loses.

Draw Conditions
Threefold repetition, stalemate, or mutual agreement (as in standard chess).

Thus we arrive at the game's essential truth:
Every capture gives your piece to the opponent.
Victory can be achieved through Sunyata (self-emptying) or traditional checkmate.
Move progression adds escalating risk/reward.

White forces Sunyata in 9 moves:

1. Kb5, Kxc5, Kb5, c5, cd, c4, c5, cd, Kxa5#

Kxa5 - King’s final capture empties White’s existence.
Sunyata achieved. White won.

Now I realize I’d been designing this game for years.
At first, as a puzzle. Then - as a philosophical experiment.
But when my king vanished for the first time, dissolving into black,
I felt a strange peace.
Chess that teaches not to win, but to let go.
Perhaps this is enlightenment: to capture nothing, yet hold everything.

The real game begins when we stop seeing black and white - and start seeing...

The Illusion of Control
Every capture is not a gain, but a transformation: the aggressor loses their own nature, becoming what they conquered. This mirrors the Buddhist concept of anatta (no permanent self) - even in victory, you dissolve into the other.

Liberation Through Letting Go
Winning via sunyata (losing all your pieces) is a metaphor for detachment. To triumph, you must willingly surrender everything, even the king - the symbol of ego. Like the Zen koan: "If you meet the Buddha, kill him" (free yourself even from the sacred).

Move Progression: Karma and Cycles
The alternating 1-2-3-4 move sequence mimics accumulating karmic consequences. The more moves a player gets, the higher the risk of self-annihilation (a capture spree turns their army against them). A reflection of life: the harder you strive, the closer you come to losing yourself.

Two Paths to Victory: Action vs. Non-Action
Checkmate - victory through force, control, will (the warrior’s path).
Sunyata  -  victory through surrender: emptiness and release (the monk’s path).
The game demands conscious choice: to fight or to let go - like Krishna’s teaching in the Bhagavad Gita: "Act, but do not cling to the fruits of action."

The Phantom King
The last king, changing color, symbolizes the final illusion. Its transformation reveals: even your "self" is a temporary form. Victory comes when identity itself ("white" or "black") disappears.

The Essence of the Game
This is not just a battle of wits, but a meditation on the board:
Capturing pieces = losing yourself.
To win, you must stop clinging to victory.
Here, chess becomes a koan - a paradox that shatters logic. As Lao Tzu might say: "To conquer others is strength; to conquer yourself is true power."

Tactics and Strategy in Sunyata Chess

How many moves must White consecutively play in one series to checkmate Black?

In Sunyata Chess, the classical tactics (material elimination) of Progressive Chess are transformed but not removed - instead of "destruction," a meta-game of color control emerges. This creates fundamentally new strategic layers.

Color inversion makes traditional capture (physical piece removal) secondary - the captured piece doesn't disappear but changes allegiance and even value.
Direct attacks on the king (as in Progressive Chess) become meaningless - replaced by the need to manage color dynamics.

The game now operates on two levels:
Positional play (as in standard chess)
Color management (deciding when and which pieces to invert)

Sunyata Chess doesn't eliminate Progressive Chess tactics but elevates them to a new dimension:
Instead of destruction - transformation
Instead of checkmate - color control
Instead of brute force - subtle manipulation

This makes the game more abstract yet deeper. While unfamiliar to classical Progressive Chess enthusiasts, Sunyata Chess becomes the perfect choice for those seeking new intellectual challenges.

Solution
White checkmates Black in six consecutive moves:
Nc3, Nd5, Nxe7, Rg1, Rxg7, Nf6#

Note that Black cannot capture the white knight with Ng8xf6, since this capture would result in the black knight becoming white and, accordingly, the black king would remain in check.