1) Strong in battle 
having strong weapons; militarily potent
• (a.) Powerful in arms; mighty in battle.
Ar·mip'o·tent adjective [ Latin armipotents ; arma arms + potens powerful, present participle of posse to be able.] Powerful in arms; mighty in battle. « The temple stood of Mars armipotent . Dryden. » 
armipotent 1. The power in arms; a term originally associated with Mars, the Roman god of war. 2. Powerful in arms; mighty in battle.
strong in battle.