Acid Ants are rare, predatory insects native to hot climates, especially jungles and rainforests. Each one is the size of a small dog, standing up to 18 inches tall, 32 inches long and weighing up to 25 pounds. Acid Ants have undifferentiated circulatory and digestive systems; vital nutrients are delivered throughout the body between bile ducts under the carapace which continuously generate a highly corrosive bile that must be frequently expelled when not eating, or the build-up in pressures can create fissures or even explosive ruptures. Acid Ants use this corrosive vomit to dig extensive networks of underground tunnels and clear the vegetation around their colonies. An Acid Ant colony is recognizable by a large clearing in dense forest where only clear soil is visible, from which dirt mounds four to five feet tall extrude tunnel entrances.
Acid Ants operate in groups known as hives, taking on extra intelligence and cunning. When hunting or defending their colony they will attack in distinct groups, melee shock troops rushing their prey to attack with their mandibles while ranged attackers spewing corrosive vomit in streams arcing up to 80 feet away.