What a battle card is for
A battle card exists to prepare a seller for one specific competitive conversation. Its constraint is time: it is read in the minutes before a call, so anything that cannot be absorbed and used in that window does not belong on it. That constraint is what makes battle cards useful and what most versions of them ignore.
One card covers one competitor. A single document covering every competitor is too long to read before a call and too general to help during one, which is how competitive material ends up being replaced in practice by whatever a colleague said about their last deal.
