The Discovery of FEN Mapping Symmetry
For weeks I had been trying to make the wrestlers move on the chessboard, mapping joints to squares and squares to motion. Then, by accident, I discovered something that changed how I thought about both chess and animation. To test the results you can analyze lichess games with my FEN-OX Analyzer and then read the rest of the blog.
In the first two blogs, I described how I found wrestling chess connection when I mirrored the white pieces on ranks 1 and 2 and the black pieces on ranks 7 and 8 into the middle of the board: I placed all white pawns on rank 4 and all white pieces on rank 3, in exactly the same order as their starting formation. I did the same for black, their pawns on rank 5 and pieces on rank 6, symmetrically reversed.
Forfoots = Pawns E and D. Ankles = Pawns C and F. Knees = Pawns B and G. Hips = Pawns A and H. Shoulders = Rooks. Palms = Knights. Elbows = Bishops. Torso = King. Neck = Queen.
I then created an imaginary space consisting of 64 cubes – meshes arranged in 4 sets of 16 cubes.
When a white piece moved from rank 1 or 2 to rank 3 or 4, the FEN mapping for those central ranks provided an exact destination, an anatomical extension of its original square. For instance, if the e2 pawn, mapped to the right forefoot, advanced to e4, that square represented the right forefoot in the same body schema. The mesh moved forward and occupied the imaginary right forefoot of the second wrestler.
If the same pawn crossed into rank 5, it entered the imaginary black mapping zone, adopting coordinates from the opponent’s body layout. Going to e6 which correspond to left forefoot of the black wrestler means that right forefoot of white wrestler occupied the space where black’s left forefoot could step, so preventing black wrestler stepping forward with his left foot, creating a natural collision of structures.
The chessboard thus was transformed into a set of 64 cubes. Each chess square became a cube labeled as a particular body joint.
This meant that chess moves could now be read not only as formal 2D transitions, but as anatomical spatial transformations. I called each set of those 16 cubes a wrestler. The figures for ranks 1,2 and for ranks 7 and 8 called real wrestlers, those between them are imaginary wrestlers. In a wrestling analogy white imaginary wrestler corresponds to real wrestler one step closer to black.
A Combinatorial Universe of FEN Variants
The chess variant I describe is perfectly legal chess to meshes isomorphism. The only difficulty of producing moves in 3d chess is to constantly look up the FEN structure for ranks 3-6. I will not try to prove mathematically that it is an isomorphism, but intuitively it is. The key to preserving isomorphic map is make navigating black ranks by white pieces in the manner they were defined by black.
Because I initially chose the arrangement of pieces on ranks 3-6 naively, translating forward all white pieces and all black pieces which would correspond to making one step forward for both sides wrestlers, I did not have time to think about this in more general terms. But eventually I grasped the problem. There are many more ways to create chess to 3d meshes isomorphic animations. Once I understood this, the scope of possibilities exploded.
Any configuration in which all 16 white pieces are placed somewhere on ranks 3 and 4, and all 16 black pieces are placed on ranks 5 and 6, defines a legal, rule-preserving variant of chess when this mapping is used as a dictionary for chess to meshes animations of 64 cube meshes. The total number of such mappings is enormous: 16! × 16!.
But when every pawn and piece, knight, bishop or rook, is labeled as a specific body part with a side attached, the permutations become biomechanically distinct variants. Each mapping defines a new rule set for how anatomy and logic interact.
FEN is not just notation — it’s anatomy. Each arrangement is a genetic pattern for how logic, motion, and structure interact. From here, everything else, the idle animations, the joint groupings, the event-driven motion, grew out of this one insight.
The Logic of Penetration
In wrestling, everything revolves around penetration, the art of entering the opponent’s space. It’s not about brute force; it’s about timing, geometry, and anticipation. Penetrating your opponent’s structure, whether slipping your right palm into an underhook grip or driving your knee behind their balance point, is never simple. Your opponent won’t just allow it.
Chess has vaguely similar penetration logic. A pawn breaking past the fourth rank, or a knight establishing itself deep on the sixth, is a rare and dangerous event. These are not casual moves, they represent successful entries into the opponent’s defensive body.
When Penetration Becomes Visible
What makes my 3D variant so fascinating to watch is that these penetrations are no longer abstract, they’re visible anatomical invasions. When a white pawn or bishop enters the fifth or sixth rank, it’s not just advancing, it’s physically crossing into the imaginary structure of the opponent’s body. The mapping exposes how hard and how rare true penetration is, both in wrestling and in chess.
This is why the FEN-based mapping isn’t just a technical curiosity, it’s a bridge between two ancient systems of logic: the tactical geometry of chess and the kinetic geometry of wrestling. Both are about movement through resistance, about finding the line of least opposition through structure.
When Code Starts to Move Like Muscle
In the first blog, I described how the entire project began with a single FEN mapping, a small, almost accidental discovery that chess notation could define anatomical structure. That was the moment the idea of chess-wrestling isomorphism was born. In the second blog, I stepped away from the keyboard. Instead of programming, I tried to think like a wrestler and to explain the logic of real attacks in chess terms.
Now, in this third stage, I’m back to building code again, but this time, the goal is interaction. I wanted people to be able to watch real chess games through the lens of this variant, to connect live logic from the chess world to the embodied, physical logic of the wrestlers. So I connected the system to Lichess and built a web interface that lets anyone enter a game ID and replay a match in this new language of motion.
The wrestling stance no longer has to be perfectly symmetrical as it was in the first experiments. You can now adjust parameters like extend, lean, squat, and separation, fine-tuning the wrestlers’ posture in real time.
The Flying Chessboard Analogy
A more interesting find is to imagine a flying, flexible chessboard. The board itself can tilt, ripple, and float in 3D space, but the pieces, the wrestler’s joints, remain locked to their coordinates on that moving surface. Wrestlers constantly move, sway, breathe, and shift rhythmically, yet the actual attack geometry should remain exact. These idle motions of the chess board do not have any effect on chess game if the pieces are glued to the board and do not fall off.
So while the underlying code ensures that a pawn still moves one square forward, the animation makes that advance look like a step, a shift of weight, a pulse through the entire structure. The chessboard becomes a stage, the wrestlers its moving grid.
The Tools: The FEN-OX Analyzer
On the analyzer page, FEN-OX Analyzer, you can type in a Lichess game ID and instantly watch it unfold as a 3D wrestling sequence. Before you start, you need to select or load a FEN mapping, the genetic layout that defines how each chess square corresponds to a body joint. You can use one of the pre-set symmetrical FENs, or design your own.
The stance no longer has to be perfectly symmetrical as it was in the first experiments. You can now adjust parameters like extend, lean, squat, and separation, fine-tuning the wrestlers’ posture in real time. This flexibility makes each replay unique, part analytical tool, part choreography generator. The analyzer isn’t just a viewer; it’s a sandbox where logic becomes body language.
From Symbol to Gesture
At this point, the system has grown into something more than software. It’s a medium where strategic thought and physical motion mirror each other. Every match imported from Lichess isn’t just a record of moves, it’s a story of two structures testing each other’s boundaries. Because each game is replayed through the FEN-OX mapping, it becomes a form of visual reasoning, a choreography of penetration and defense, of balance and collapse, of order finding its limits through motion.
The next step will be to let these wrestlers not only follow games, but learn from them, to evolve their own movement patterns, to find new geometries of interaction through self-training and data from millions of chess matches.