Does the chariot's value change between the opening and the endgame the way the horse's and cannon's do?
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
Not much, compared to the other pieces. A chariot's unblockable straight-line movement means it is roughly as dangerous in a crowded opening position as it is in a bare endgame. That is a real contrast with the horse, which grows stronger as the board clears of blocking pieces, and the cannon, which grows weaker as its supply of screens dries up.
Why the chariot is the stable one
Nothing about a chariot's movement depends on how many other pieces are on the board. It is blocked by whatever sits directly in its path either way, and its reach along an open file or rank is the same whether that file is one of nine on a full board or the only thing left standing in a bare endgame.
What this means for trades
Because the chariot's value is roughly constant, trading it early is closer to giving up its full long-term worth than trading a cannon or a still-developing horse is. It is also why a chariot is almost always the most valuable single piece to keep when simplifying toward an endgame.
Related questions
Does the chariot ever get weaker as pieces come off the board?
Only slightly, from having fewer targets to attack; its actual mobility and reach do not decline the way the cannon's does.
So is the chariot always worth trading a horse and a cannon for together?
Not automatically, the exchange still depends on the position, but it is a fair general guide when nothing else stands out.
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