The great Librarius Omnis, also known as the Libraries Omnis, is a subterranean, continent-spanning library located beneath the sands of Mars which contains vast information from Mankind's history stretching back to the Dark Age of Technology. It has been the subject of several Techno-archaeologist expeditions over the millennia. According to legend, at the dawn of the Imperium of Man, the legendary Techno-archaeologist Arkhan Land led an expedition into this labyrinth of catacombs that lasted for three standard years with the intention of finding an intact and functioning Standard Template Construct database. During his long sojourn beneath the surface of sacred Mars, his expedition mapped a region of the catacombs equivalent in size to a small nation.
Ultimately, he did not succeed in this quest, but made two discoveries which were to revolutionise Imperial technology for millennia to come. The first of these was a near-complete dataslab image of STC information pertaining to a heavily armoured main battle tank, named the "Land" Raider in honour of its originator. Secondly, Land unearthed valuable information on the design and manufacture of anti-gravitic plates, leading to the construction of the first "Land" Speeders.
When he returned to the surface of the Red Planet, Land also possessed extensive plans for the Crawler Pattern agriculture harvester. His awed superiors requested that he give a presentation on this design to various worthies from the most important Forge Worlds. The new vehicle was not merely efficient in its use, it was also an icon of the trifecta of mass-production utility: inexpensive to construct; simple to maintain; and easy for untrained users to safely control. Its use would greatly improve productivity on the newborn Imperium's Agri-worlds in the generations to come.
Arkhan Land met his end leading a second expedition into the Librarius Omnis. It is believed that he and his party were picked off one by one by some mysterious predator, although it is still a matter of much debate whether this was some kind of living beast, a psychic entity or perhaps even a sentient virus. For most, it is simply proof that the secrets of the Dark Age of Technology are best left to lie undisturbed.
- Codex Adeptus Astartes - Space Marines (8th Edition), pg. 90
- Imperial Armour Volume Two - Space Marines and the Forces of the Inquisition, pp. 83, 117
- Imperial Armour Volume Two (Second Edition) - War Machines of the Adeptus Astartes, "Adeptus Astartes Land Raiders", pp. 27-29, 37, 50-51
- White Dwarf 246 (UK), "Steel Chariots - The Space Marine Land Raider"
- The Master of Mankind (Novel) by Aaron Dembski-Bowden