Fomicry

Caution: Spoilers Ahead!!

Fomicry: What It Is
Fomicry is a means to replicate anything. The most common use in-game is the replication of human people, such as Luke Fon Fabre and Fon Master Ion.

History
Fomicry was first created by Jade Curtiss and Dist the Runny Rose (Then Saphir Wyon Neis). As a child, Jade did not understand the meaning of life and death and so he performed many experiments on smaller animals to fix this. Along the line, instead of better understanding death, he found a way to "cheat it". This was the birth of Fomicry. The first known example was performed by a nine-year-old Jade to his sister, Nephry's doll, "Millie". it was at this point that Nephry later told Luke that "She felt something abnormal in his way of thinking." The second example was the famous death of Jade's professor, Gelda Nebilim. Though, when he actually attempted Fomicry on a real human being, it drastically backfired and the real Nebilim died.

There was also a third time in the new manga, "Jade in my Memories" or "Tsuioku no Jade", that he and Dist used a Fomicry device to rebuild a lock they had snapped on their dorm gates.

Father of Fomicry
Contrary to popular belief, Jade was not the only one to create fomicry and, in fact, only did half the work.

To his credit, Dist was a brilliant young boy in his day and created many small machines as a hobby. When Jade and Dist joined the military academy, Dist began to create the machines which would be used to house the mechanisms that did the work of replicating in the later years (before, they just used a glyph). All the current Fomicry machines are assumed to have been built by Dist or have been built according to Dist's plans.

Jade, on the other hand, supplied all the theories and practices that Fomicry is done by. This is most likely why he is accredited as the Father of Fomicry. It has also been known that he is the one who has written books on the matter (like the side quest where they search Van's office).

The Ban
After an accident in the lab Jade was working in (Explained in the Jade manga; there's a small scene for it in the anime as well), Jade banned Fomicry because of the ethical and moral implications that came with it - especially that of replicating human beings. It was after this that he stopped attempting to resurrect the professor and where he and Dist broke off from each other (Seeing as Dist was still convinced he and Jade could do it).

Use in-Game
The foremost use in-game is the replication of Asch the Bloody (formerly known as Luke Fon Fabre) and Ion (Who is actually the Seventh replica of the former Fon Master Ion. Others include Sync the Tempest and Florian)

The second larger use is in Van's final plot for Auldrant, including replicating the entire Island of Hod itself to create "Eldrant".

A smaller use of Fomicry is seen in the replicated Cheagle named Star, which you pick up from Ortion Cavern while looking for Tear Grants.