How does Counter Attack work: which orders, which section, and can it copy another Counter Attack?

Question

Accepted Answer

It answers one command card of your choice and copies its order. Section and Inspired Leadership cards are mirrored (left becomes right); for Leadership Any Section your orders must be in the section your opponent chose. It can be played on a Counter Attack, but not on First Strike. Counter Attack is played in the normal turn sequence, not during a combat. The designer plays an unofficial variant where a leader in any section works; the printed rule remains the official one.

Commands & Colors: Ancients

How does Counter Attack work: which orders, which section, and can it copy another Counter Attack?