Artilleryants are soldiers specializing in ranged combat.
They have a deposit of formic acid and a sting in their gaster that allows them to sting or spray their enemies. It is very effective for scavenging predators.
But their true power is unleashed in the massive battles as they launch a devastating acid rain on the enemy that causes great casualties. On the other hand, it is a caste that is not qualified for melee combat.