According to Ephesians 6:12, our struggle is not against flesh and blood but against what?

Answer: Spiritual forces of evil

Paul says our struggle is against the rulers, authorities, powers of this world's darkness, and spiritual forces of evil in the heavenly realms.

“For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this world’s darkness, and against the spiritual forces of evil in the heavenly realms.”— Ephesians 6:12 (BSB)