The Marys are more than myth and above legend, whispered about quietly by a very small community that has made contact with the elusive quadruplets and lived to tell the tale. There are no pictures, no video, no written accounts or audio recordings of The Mary's in existence on any piece of network capable hardware as records of their presence is aggressively purged faster than it can be propagated. This infallible protection of their identity is so complete that Interpol's own secret, special task force assigned to the Mary's once concluded that an AI was the only entity capable of the feat before the team was deemed a drain on vital resources and the members split into separate task forces.
The most common accounts traded privately behind closed doors talk of four identical sisters age 10 to 14 each with their own special skills or abilities that border on the supernatural. Despite their appearances, sparse sampling of two of the sisters' DNA suggests that they aren't even related - they also reveal a level of genetic complexity that borders on in-human but without the tell-tale signs of genetic manipulation or engineering.
The Quiet One
Most often the face of any peaceful interaction with the Marys, the sister sometimes referred to as The Quiet One is confirmed to be a world class infiltrator. She seems to be the most mentally focused of the four and suffers from no obvious quirks or deficiencies.
The One In Back
Usually hanging back behind the group, the sister most often called The One In Back appears to handle the technology (some of which appears to be decades ahead of current military hardware) and cover escape routes while supporting conflicts from afar.
The Strong One
The most childlike in her manners and the most likely to speak with strangers, The Strong One is almost certainly encountered wearing little or nothing for reasons that have yet to be determined. Eye-witness accounts of her lifting as much as 16,000 lbs without strain are criticized as gross exaggerations by some but are corroborated by evidence in the form of brutal violence left in her wake.
The Sad One
By all accounts, The Sad One doesn't seem to ever want to be wherever her sisters are and has been observed in every stage between and including obvious physical discomfort and intense, physical pain. Though they cannot explain why, the few who have survived conflict with the Marys all targeted The Sad One first, often for dubious reasons. Evidence suggests that she is an exceptional Magiker and a conflict with her should be avoided at all costs.