OGC:Turret Chain Fire (5e Variant Rule)
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Turret Chain Fire
Turret guns are susceptible to chain fire, but their unique configuration gives them different rules. When a creature using a turret gun rolls a 1 on its attack roll, the spark ignites all shots. Given that one or more shots are pointed at the creature, the creature suffers damage as if it’d shot itself in addition to the normal fouling of the barrel due to a misfire (a GM may ignore this and impose only the misfire if the turret gun only had 1 or 2 chambered bullets left).