The EM pulse cannon was a type of weapon, a directed energy weapon that fired a pulse of electromagnetic energy discharge.

This principle was adapted as a hand-held weapon held weapon of Grigari manufacture that was easily capable of killing enemies; whether its an organic being or a Grigari itself. They fired powerful electromagnetic cores to accomplish this task.

The Grigari also used EM pulse cannons as ship-mounted batteries on their warships in order to disable and board other starships. In 2374, the Bajoran research vessel Ke'el Tul, the USS Defiant and Starbase Deep Space 9 were all disabled by Grigari EM pulse cannons. (DS9 video game: The Fallen)