Breakthrough and encirclement manoeuvres are resolved by both squadrons rolling 6+ on 2d6.
How it works
Diekplous: an attacker in epi pollon or epi keras contacts an unengaged enemy in epi mias. Attacker-only success places it in the defender's rear for an immediate melee; both succeeding pushes it back 6 inches; any failure disorders it and starts a melee. Periplous: line against line. Attacker-only success puts it on the offshore flank; a tie sends both racing offshore in column each turn until one wins, possibly off-table with losses. Crew, ship (fast/heavy) and disorder modifiers apply, and green or disordered squadrons cannot attempt either.
If only the attacker is successful, diekplous has been performed! Place the attacking squadron in epi mias in the defender’s rear and immediately fight a melee.



