What does the saying 缺士怕車，缺象怕炮 mean?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws for movement, checkmate and both repetition rulings: a side that forces a repetition by perpetual check or perpetual chase loses rather than drawing. The chase half has not been validated against the official casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it before publishing.
Direct answer
The saying means "missing advisors, fear the chariot; missing elephants, fear the cannon". It sums up which attacker is most dangerous against which damaged defence. A defence without its advisors has lost the pieces that guard the points right around the general, which a chariot exploits. A defence without its elephants has lost the pieces that most often stand on or move across a cannon's lines, which a cannon exploits.
Missing advisors: the chariot's chance
Advisors sit on the palace points next to the general. They block checks along the short lines inside the palace and keep the general's neighbours covered. A chariot attacks whole lines at close range, so once those palace points are empty it can check from beside or in front of the general and, with the attacking general's help, take away escape points one by one. For how thin that defence is, see defending with advisors and no elephants, the reverse case.
Missing elephants: the cannon's chance
A cannon needs exactly one screen. Defending against it is largely about controlling the count of pieces on its line: adding a second blocker, or moving the screen away. Elephants are the defender's most useful spare pieces for that job, since they stand in front of and beside the palace and can move between several points. Without them, the defender has fewer ways to change the count, and cannon attacks through the palace, often using the defender's own advisors as screens, become hard to meet.
How players use it
The saying is a guide for trading. If your opponent is missing advisors, keep your chariot. If they are missing elephants, keep your cannon. And when you choose which of your own defenders to give up, think about which attacking pieces your opponent still has. The underlying difference between the two defenders is covered in losing an elephant versus losing an advisor.
Related questions
Is the saying always true?
It is a rule of thumb, not a verdict on any specific position. The details of each endgame still decide the result.
Does it apply in the middlegame?
Yes, as a guide to which attacks to prepare, though it is quoted most often about endgames.
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