The empusas are a species of giant mantises found on the minor island of Hekuba. When empusas first hatch they are roughly the size of a house cat, but after several years of molting followed by six months of metamorphosis they can grow as large as small ponies. An adult empusa is able to alter the pigment in its exoskeleton in a matter of minutes, allowing it to become nearly any color needed to conceal itself. When this color camouflage is combined with the uncanny ability to remain motionless for hours on end, a pack of empusa is capable of ambushing livestock, entire flocks of birds, and even people. Discarded empusa exoskeletons permanently turn a shiny black and are sought after by Hekuban tailors to craft the light and flexible armor of the island's female soldiers.
Empusas have enormous cultural significance to the Hekubans and adorn everything from pottery to the royal crest. The oldest and most well known Hekuban fable, The Jade Empusa, is the tale of how the first queen of Hekuba came to defeat her rivals and unite the island by learning "the way of the empusa". The current matriarch, Queen Ofelia, believes that the Empusa have military potential as aerial mounts, much like the Ruqs and Ruqriders of Sha-ka-ruq. However, wild empusa are too small to carry a rider and too temperamental to be tamed. For this reason, the Queen is seeking the aid of alchemists and koldun to help breed larger empusas capable of being domesticated.
Supposedly there is a close relative of the Hekuban empusa which lives and hides in the Wheeltrees of the jungle sky, but a reliable sighting has not been reported for nearly a decade.