diff --git a/docs/superpowers/plans/2026-05-19-duplicate-chess-sandbox.md b/docs/superpowers/plans/2026-05-19-duplicate-chess-sandbox.md
index cb65956..16b1e13 100644
--- a/docs/superpowers/plans/2026-05-19-duplicate-chess-sandbox.md
+++ b/docs/superpowers/plans/2026-05-19-duplicate-chess-sandbox.md
@@ -496,12 +496,12 @@ describe('legalSyncedMoves', () => {
   });
 
   it('excludes a move legal on only one of the player\'s boards', () => {
-    // N e2e4, S e2e4, E e7e5, W d7d5  -> NW black has pe5, NE black has pd5.
+    // N e2e4, S e2e4, E d7d5, W e7e5  -> NW black has pe5 (W's), NE black has pd5 (E's).
     const g = new DuplicateGame([
       { player: 'N', from: 'e2', to: 'e4' },
       { player: 'S', from: 'e2', to: 'e4' },
-      { player: 'E', from: 'e7', to: 'e5' },
-      { player: 'W', from: 'd7', to: 'd5' },
+      { player: 'E', from: 'd7', to: 'd5' },
+      { player: 'W', from: 'e7', to: 'e5' },
     ]);
     expect(g.currentPlayer).toBe('N');
     const keys = legalSyncedMoves(g).map((m) => `${m.from}${m.to}`);
@@ -525,8 +525,8 @@ describe('selectionHighlight', () => {
     const g = new DuplicateGame([
       { player: 'N', from: 'e2', to: 'e4' },
       { player: 'S', from: 'e2', to: 'e4' },
-      { player: 'E', from: 'e7', to: 'e5' },
-      { player: 'W', from: 'd7', to: 'd5' },
+      { player: 'E', from: 'd7', to: 'd5' },
+      { player: 'W', from: 'e7', to: 'e5' },
     ]);
     const h = selectionHighlight(g, 'e4'); // North's e4 pawn
     expect(h.boardA).toBe('NW');