The Sting Boys

Not much is known about the Stings Boys, but we only have one line to use to make assumptions with.

"My dad owns the volcano, and he will call his sting boys to get you!"

This line is presumed to be from a Fire Type child Etheiran, hence the father owning the volcano. Their dad might be a final stage Fire Type, or Ignititan, while the Sting Boys may be a group of Stingfernos, due to working for the owner of the volcano, and that being where Magmarva spawns.

In another RP there was a Kindite and his father, Ignititian. These two may be the person who said this line, and the father.

So in theory, a Kindite child threatened some other Etherian, and told them about their father, Ignititan, and that he'd send the Sting Boys after them.