चत्वारो दुर्जयः ॥ कZ_१०.६.२२ ॥
catvāro durjayaḥ
ດັນດາ 4 ແຖວ ກໍ່ເປັນຮູບແບບ «Durjaya» (ຍາກຈະຊະນະ)।
Redundancy and depth: multiple mutually supporting units reduce single-point failure—an administrative logic applied to battlefield organization.