Can the general be part of a fork alongside another piece?
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
Yes. A horse, cannon or chariot move that checks the general while also attacking a second piece is a fork in every meaningful sense, and it is an unusually effective one, because the check must be dealt with immediately. The defender rarely has time to also save the second piece, which is usually just lost.
Why forks on the general are so much stronger than ordinary forks
An ordinary fork against two pieces at least gives the defender a choice of which one to save. A fork that includes check removes the choice entirely: capturing, blocking or moving the general has to happen first, and only then, if anything is left over, can the second target be addressed, usually too late.
Where this shows up most often
A horse landing on a square that checks the general while also attacking an undefended chariot is the classic version. It is one of the reasons horse checks are worth calculating carefully before dismissing them as merely annoying.
Related questions
Is this different from a discovered check that also wins material?
Related, both combine check with a material gain. A fork does it from a single piece attacking two targets directly, while a discovered attack uses two pieces working together.
How do I defend against this specifically?
Before allowing a piece to reach a square that could check your general, check what else it would attack from there too, not just whether the check itself is dangerous.
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