पत्त्यश्वरथद्विपानां पूर्वं पूर्वमुत्तरेण घातयेत् हीनाङ्गमधिकाङ्गेन चेति ॥ कZ_१०.६.४४ ॥
pattyaśvarathadvipānāṃ pūrvaṃ pūrvam uttareṇa ghātayet hīnāṅgam adhikāṅgena ceti
Of infantry, cavalry, chariots, and elephants: one should strike each earlier arm with the one that follows it (i.e., infantry with cavalry; cavalry with chariots; chariots with elephants)—that is, the weaker arm with the stronger (or more capable) arm.
It formalizes superiority matching: apply the arm with greater mobility/shock/protection to neutralize an inferior arm, conserving effort and reducing attrition.