Halo is ostensibly a series about using guns to shoot aliens and defeat organized religion. But the coolest weapon in the series isn’t a gun. It’s a sword — specifically, it’s the energy sword.

A good many of us whiled away the hours of our youths playing Swords Only deathmatch in Halo 2. The Energy Sword, aka the Plasma Sword, was the star of the show, with its devastating glowing ...