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From the preview:
Franklin Experimental Brigade's Coil Projector is one of the many arms innovations of the Union for the War.
The FEB is comprised of fearless veterans with a proven military background and a burning zealotry for the cause of the Union.
These soldiers wade into battle clad in specially quilted uniforms, engineered to prevent the electrical currents they harness from backfiring onto the wielder. On their backs, they carry bulky power packs that store the energy needed to fire their weapons.