unmask one's batteries

== English == === Etymology === From the revealing of artillery previously concealed from the enemy’s line of sight, immediately before opening fire. === Verb === unmask one's batteries (third-person singular simple present unmasks one's batteries, present participle unmasking one's batteries, simple past and past participle unmasked one's batteries) (idiomatic, dated) To begin a decisive action, especially one that reveals one’s true strength or character. Used other than figuratively or idiomatically: see unmask,‎ battery. ==== See also ==== cross the Rubicon show one's cards