// HACKER NEWS — CYBERSECURITY
I asked astra to make playable 4D chess
The goal is still checkmate. White moves first. Select a piece, then a marked square. A solid dot is an empty destination; a ring marks a capture. In computer mode, choose White or Black using the side selector.
Think of a 3D chessboard as layers of ordinary boards. X and Y locate a square within a layer; Z chooses the layer. Here, each 3D board has two 4 × 4 layers.
Now make a second copy of that whole 3D board. W chooses which copy you are in. Every square has a corresponding square in the other copy. A move along W changes copies while keeping X, Y, and Z the same.
In the tesseract view, W = 0 is the inner cube and W = 1 is the outer cube. Both represent equally sized spaces. The inner cube looks smaller because of the projection. W is another spatial direction; it does not mean time.
a1 [0,1] means file a, rank 1, Z = 0, W = 1. That is a1 on the top-left board.
Choose a piece, then play or scrub through its move. These cleared-board examples use this game's rules. Other 3D chess variants may define their pieces differently.
Drag either drawing to rotate both. You can also focus a drawing and use the arrow keys. Home resets the views.
These diagrams illustrate movement. In your game, pieces along a sliding path block it, and every move must keep your king safe.
Judge a move by its coordinates. A W move can look diagonal in the drawing and still count as a straight rook move. Rotating the view changes how a move looks, not whether it is legal.
Any bishop or queen move involving Z or W is at most one step long on this board. Those axes only run from 0 to 1. X and Y each have four positions.