Fire beetles are one of the ur-vermin of RPG ecologies. Giant stag beetles are National Geographic gone Carboniferous.
A theater is renowned for its special effects. The lighting master’s secrets are his caged fire and flash beetles. Their constant use has made them a bit temperamental and occasionally nippy, causing the cast to loathe them. The theater has also suffered damage when the lightning master has accidentally mistaken a mining beetle for a fire one—the larger bug’s ability to burrow making it quite the escape artist.
Loggers hate giant stag beetles, but certain forest gnomes love them. If kept fat with decaying wood, they train easily enough, and the beetle’s young male riders are as eager to show off their mounts’ antlers and jousting prowess as the stag beetles are themselves.
An alchemist has a particularly nasty alarm system. Every time he opens the front door—and only for appointments—he tosses some produce into the cage containing his pet bombardier beetle. Anyone else opening the door has only a round to act before receiving a spray of acid.
—Pathfinder Bestiary 33