The general rule in chess is that pieces cannot capture other pieces of their own color. You cannot “self-capture” from your own team.
It sounds silly, because why would you want to? Usually that would just be losing your own material, making your position worse (except in “Suicide Chess”). But there are a few cases where it would be big advantage to be allowed to capture your own pieces, such as where the enemy is using a shield of your pawns to protect their King (see “hiding the King in front of enemy pawns”). But it’s not allowed by the rules.
Related Chess Rules Topics
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