Black Knight / White Knight
A white knight is described as someone who saves a company from a hostile bidder. When, after the takeover, this white knight turns around and does the same as the hostile bidder, they are called a black knight. In lore, black knights usually portray villainous figures who use anonymity for misdeeds and are contrasted with the white knight-errant, known for coming to someone's aid.
Why it matters
Moving away from terms which infer positive or negative connotations associated to colour and colour binary (e.g. Black = Bad and White = Good) to distance from cultural views of good & evil, especially related to skin colour or appearance. Specifically, this associates 'black' with a bad person and actions.
Instead try saying:
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