accordA study in support

Tap a piece, then a dotted square. Rook (R): straight lines. Bishop (B): diagonals. Knight (N): an L, two squares then one. King (K): one square in any direction.

Defended means another piece could reach your landing square using its chess movement. Rooks and bishops cannot see through pieces; knights jump.

Unlike chess: no captures, opponents, turns or check. Only the moved piece must be defended after a move. Pieces can leave their marks. All pieces must be on their own marks together; any move count wins.

Tab into the board; arrow keys move focus. Enter or Space selects or moves. Escape cancels. U undoes; R resets. Undo is unlimited. Targets are proven shortest solutions.