Piranha Ant

One piranha ant, barely an inch long, looks too trivial to notice. Its head is oversized for an ant and its mandibles are serrated, and its dull gray or black color lets it vanish against stone, street dirt or shadow. The threat is the colony: thousands strong, fearless, and able to reduce a man to a skeleton within minutes.

Piranha ants only attack victims who do not see them coming, usually waiting until the target is sound asleep, which guarantees at least one free round from surprise. The whole colony flows over the victim at once, each ant tearing off a scrap and moving aside for the next. Treat the swarm as one large creature that hits automatically every round thanks to its sheer number of bites. Damage is 1d4 multiplied by the victim's Armor Class. Because they study their targets in advance, they generally leave alone anyone with AC 0 or better.

Each point of damage dealt to the swarm kills 1d20 ants, but a colony numbers 1d20 x 1,000, so running away is usually easier, and safer, than fighting.

A colony is nomadic, settling for a while in some large building. A slightly oversized queen handles egg-laying, a few winged males (fly 12, maneuverability C) accompany her, and almost all the rest are sterile female warriors. The entire colony shares one mind: every ant knows instantly what the others know, and attacks are coordinated with chilling precision.

That shared mind makes them worse than jungle army ants, because they can plan. Scouts comb the city for good targets, preferably people who live alone. The colony then moves into the victim's building, hiding inside the walls or in disused cellars and attics, while scouts track the occupant's habits. When the moment comes, typically once the target is asleep for the night, the ants pour silently into the room together. Most victims die before understanding what is happening. The ants eat every scrap of flesh and slip away as quietly as they arrived.

Winter drives the colony into some hidden refuge. The queen lays through the cold months, the eggs hatch by its end, and after a short larval stage the young seal themselves in cocoons and emerge in spring ready to swarm.

Piranha ants work hard to leave no evidence; usually only a bare skeleton marks an attack. Survivors eat their own fallen, which both feeds them and keeps anyone from finding dead ants and guessing the killer. Many animals eat a stray ant, but nothing dares a whole colony, so they answer to no predator.