Can a general legally move into a check that isn't obvious, a hidden discovered check?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
No, that square is simply illegal. Checking a candidate move tests the position that would result from it, against every attacking piece on the board, not just the one piece that was giving check before. If stepping to a square uncovers an attack from a piece that was previously blocked, perhaps by the general's own body, that square is refused exactly as if the attack had been obvious from the start.
Why it is easy to miss over the board
A defender under pressure naturally focuses on the piece that is checking them right now, and scans nearby squares for anything else obviously dangerous. A piece sitting two or three squares further back on the same line, currently blocked by the general itself, is easy to overlook precisely because nothing about it looks threatening until the general actually moves there.
How to check for it safely
Before settling on an escape square, trace every straight line and diagonal running through it back toward your own pieces, not just toward the piece already giving check. If your own general's departure would open a line to an enemy chariot or cannon with a ready screen, that square was never a real option.
Related questions
Is this the same idea as the flying-general rule?
Related but not identical. Flying-general is one specific case of this; the same self-check test applies to any piece, not only the enemy general.
Can this turn an apparent escape into checkmate?
Yes. A position that looks like it has an escape square can be mate once every hidden attack on that square is accounted for.
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