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Play locally against the built-in engine.
Google it. Docs only available for light-speed mode.
In light-speed mode, information takes time to travel. You can only see what your pieces can observe.
Your opponent's moves become visible based on how close your pieces are to what happened. If your knight is 3 squares from where your opponent moved, you'll learn about it in 3 turns. The closer your pieces, the faster you get intel.
You can take your opponent's pawn without them seeing it — if none of their pieces are close enough to the capture square. The pawn will simply vanish from their view. They'll figure it out eventually, but not right away.
The same rules apply to you. Your opponent (or the CPU) sees the board through their own fog of war. If you move a piece far from their scouts, they won't know what you did.
Moves you can't fully see appear as ? in the move list. You might see ♘? (a knight moved, but to where?), ?xe4 (something captured your e4 pawn), or ??? (complete mystery).