Mavros butterflies (term derived from the Greek mavros = black, although their colors range from black to dark blue and purplish hues) are an invasive species of magical insect. They have no natural origin, but were the result of an alchemistic experiment. The name of the original conductor has been lost to history. Their size varies from slightly larger than a flea towards that of a hummingbird, and exemplars about the size of an adult human hand have been sighted, albeit rarely.
Mavros butterflies are infused with ancient binding magic that forces them to form a bond with whoever captures or breeds them. Their extraordinary coloring is a byproduct of this magic, which entered the genetic code of the first mavros butterfly specimen and is since then carried by their offpring. They are naturally driven to build swarms, and a mavros butterfly swarm has one collective mind. Members of the swarm can read the mind of their owner - provided the impulses given are extremely simple and straightforward, more conveyed in pictures than words - as well as communicate with each other across great distances when it concerns getting the will of their owner done.
Being determined, but simple-minded creatures, they are best entrusted with very simple tasks such as the protection of an artifact, or the keeping of a prisoner. Compensating their minuscule size with speed, numbers and singlemindedness, they are singularly ferocious when it comes to protecting items or living entities. In a swarm, they are almost impossible to defeat; although their mouthparts contain no venom - at least, none has been recorded thus far - they can use their collective mass to great effect, keeping intruders at bay and obscuring their sight with their wings. Additionally, the primal magic they have been imbued with makes them difficult to kill.
Habitat & Ecology
Little is known of their actual diet, as they have been found in tombs, tower rooms and other locations with no apparent nutrition. Researchers have suggested that the bond they form with humans is symbiotic and they feed off human psychic energy in return for their servitude, which would explain both the mental connection and the ferocity they display when their 'master' is attacked. The magic bond is largely vital to mavros butterflies' existence: Should the person currently controlling a mavros butterfly swarm die, many of the smaller butterflies will likewise die from the impact of the severed bond, though stronger specimen may survive and find their way back into nature, eventually joining a new swarm. Though very few of them have in fact been seen in nature, as, true to their artificial origins, they are drawn towards human settlements and urban dwellings.
Issue: Obtaining and Breeding Mavros Butterflies
The existence of mavros butterflies presents a moral dilemma. Because they are excellently suited to keeping persons prisoner and will follow every command, their potential use for the kidnapping of innocents, torture and extortion is obvious. As a result, the official breeding of mavros butterflies has long been outlawed by many countries, although some still make use of mavros during interrogations of war criminals. This practice is considered highly controversial. In countries where breeding the creatures has been officially outlawed, it naturally follows that there is a flourishing black market for anyone eager and well-connected enough to obtain them. Usually they are sold in bunches of chrysalises a few days away from hatching.
The keeping of mavros butterflies one has found in nature is technically legal, though the local government must be notified of the find, and the owner must pledge not to use them for illegal, intentionally harmful purposes (a legal purpose would be, for instance, the protecting of someone's precious heirlooms or something similar.) Given their artifical origin, they present a singularity in nature and have no natural predators. Because of this, there have been projects throughout history to exterminate mavros butterflies deliberately, though due to their aforementioned hardiness, their speedy reproduction rate and their obvious value to the right people, this has long proved largely ineffectual.