The portal to hell starts rumbling, and a few rocks clatter from the ceiling into the portal. The demons guarding the pit stumble a little, steadying themselves on the walls."Earth magic? Big one?" "Yeah, somebody's got it. Get ready."They lift their guns and hands, tensed and ready for a fight.
They are not ready.
A horde of black creatures suddenly lurches from the portal, nearly engulfing the entirety of the purple glow. The demons on the surface stumble back in surprise. Ferals, unknown creatures, and so, so many bodies are pouring out from the portal in the cave. Too many. "Shit-!"
The ferals start crawling up the walls, writhing and screeching. Some of them are able to speak. Most of them are piling on top of each other to reach the over-reaching rock above the portal.The demons on top start firing, some of them attempting to use telekinesis and other magical powers to force them back into the portal, but there's too many. Once they reach the proper level, they launch themselves at the minors and start tearing them apart.
After desperate attempts to try and push the demons back into the portal, the order is given to fall back. Pulling out injured minors as best they can, the remaining demons blow charges that collapse the tunnel to the portal. As the injured are carted off to healers, others run off to tell the higher-ups what had happened.