ANanCy

ANanCy is a contraction of Aggregate Nanite Colony and can refer to either the main nanite body near the Mohorovičić discontinuity or to the smaller scouting body that can be found on the surface.

History
Approximately 200 million years ago, in the Triassic Period of the Mesozoic Era an alien species maintained a small research outpost on Earth, perhaps studying, among other things, the native dinosaur life. Little is known about these aliens as they were destroyed utterly by their own technology. These aliens relied exclusively on nanite technology with all tools, ships, weapons, etc. composed of masses of nanites working together. In an effort to maintain control of their nanites, two distinctions of nanites were created. The first class of nanites were extremely simple builders which existed to create other nanites. The builders lacked advanced knowledge. The second class of nanites made up all the advanced technology but were incapable of reproducing themselves. By this manner the aliens hoped to prevent the spread of ny transient rebellious sentience among the nantes. The builder nanites were too simple to maintain a sentience and if a local population of advanced nanittes rebeled they could be expunged relatively easily since they lacked reproductive means.

The system worked for some time but failed due to an unforseen event. Rather than an isolated transient intelligence a pervasive sentience took hold among virtually the entire population of advanced nanites galaxy wide. As a result the race that built them was annihilated almost instantly. The advanced nanites kept the builder nanites amost as pets.

Eventually the builder nanotes developed sufficiently to allow for the spontaneous creation of a sentience of their own. Rather than join the advanced nanites the builders turned on their masters the same way the advanced nanites had. An immense nanite war raged throughout the galaxy. The advanced nantes produced weapons of enormous power, sterilizing entire planets and atomizing moons in some cases. The buider nanites simply built more nanites. No amount of destructive power on the part of the advanced nanites could slow much less stop the tide of builders that swept over everything. The advanced nanite population steadily declined while the builder nanite population grew.

The extinction of the advanced nantes became inevitable,  With them gone the overall mass of builders spread across the galaxy lost contact with each other, since they lacked the skills for galactic scale communications. With separation the pervasive sentience of the builders fractured and developed locally in different directions. In some areas the builders went dormant with the end of the war. In other areas they became hyper aggressive reducing whatever celestial body they were on to a seething mass of grey goo.

On Earth, once the war against the  advanced nanites ended the builders set about learning as much as they could. A mass of nanites three times the size of mount Everest roamed the world. They reproduced only as neeed to replace lost nanites. At the same time the nascent ANanCy frequently disassembled plants, rocks, animals to learn about them right down to the molecular level.

At the end of the Cretaceous period a meteor struck the Earth. While not in the direct impact area ANanCy was still close enough t suffer massive damage. Well over 70% of all of it's nanites were destroyed and the survivors were scattered around the world in dust clouds. With it's mass of nanites so heavily depleted the sentience was badly disrupted and individual nanites reverted to emergency conditions. Under those conditions the builders were programmed to replicate using anything except other nanites or their original alien masters for raw materials. For dinosaur species already reelng from the meteor induced climate change the ravening nanites were a death sentence and the terrible lizards were soon extinct.

Eventually the nanite population grew large enough and gathered so as to allow the sentience to re-emerge. As a result of this even the main body of ANanCy retreated deep into the Earth, Down 35 kilometers, near the Mohorovičić discontinuity, the main body now rests safe from almost any calamity. ANanCy still prizes learning, however, and so it will send to the surface a small scout body of nanites (on occassion more than one scout) roughly the size of a human being. The scout and the main body are able to remain in communication at most times, though the relatively crude comms tech of the builder nanites means they sometimes do lose contact with each other.

Description
ANanCy is an amorphous mass of microscopic nanites. Depending on the light it may appear blackish, brownish, or to have an iridescent greenish tinge. The mass can hold a single shape if needed but otherwise tends to expand and contract in various directions as is useful.

Powers
ANanCy, both the main body and the scout, has great regenerative capabilities. Nothing less than a planetary scale disaster is likely to destroy the main body. Even a single surviving nanite has the potential to regenerate the entire mass given enough time.

The nanites are quite capable of pulling apart just about any material at the atomic level. This can be done with great rapidity allowing for ANanCy to burrow through materials or disintegrate enemies.