Quote:Mako energy is the refined form of the Lifestream - which, in turn, is the sum of the life energy of the Planet itself (hence, when people/animals/etc. die it could be said that they return to the Planet).
SOLDIER: Shin-Ra's elite military unit, itself divided into three ranks: 1st, 2nd and 3rd Class. Zack and Sephiroth are former 1st Class members. Members of SOLDIER are scouted by the company's Investigation Division of the General Affairs Department alias, "the Turks." Those determined strong enough to mentally and physically handle the program's process of being infused with mako and injected with Jenova's cells receive the treatment, gaining powerful increases in their physical and cognitive ability. As a side-effect of their mako-infusion, members of SOLDIER have a peculiar glow in their eyes; this phenomenon is called "mako eyes."
Approximately 30 years before the main events of the game began, Professor Gast excavated the creature, named it "Jenova," and mistakenly identified it as a Cetra/Ancient, when it was in fact a parasite which the Centra fought against and which was one of the main reasons why the Centra are mostly known as 'Ancients' in the game's here and now. Lifestream and Mako is, presumably, what Jenova feeds on, since she/it's been said to hop worlds, leaving each a withered husk once it's done there.
And while it's never explicitly stated (to my knowledge at least) in the material that Vincent also got the Jenova treatment, I'm making a leap of faith and assuming that this was indeed the case and he was the proto-subject for Jenova cell infusion into an adult. After all, that was the focus of Hojo's study at the time, and Vincent was an available guinnea pig. The jury's still out about Mako bombardment, since the glowing eyes that stem from that are usually in the green to blue range, while Vince's became red. I'm going to edge towards 'yay' rather than 'nay' though.
Again, the exact nature of the experiments that Zack and Cloud were victims of remains mostly unknown. There's mention of Mako bombardment and the like, hence the 'overload' bit, so again I'm making a leap of faith in assuming that Hojo was trying to furhter perfect/research the SOLDIER process - since Cloud comes out of the tests with both Mako eyes _and_ Jenova cells, despite not being a member of SOLDIER before the experiments took place. It's also why he's had a worse time adjusting to it than Zack did - Zack had already undergone the standard process when he became a SOLDIER member, so enduring the 'refinement' wouldn't have been as tough for him.
-Griever
When tact is required, use brute force. When force is required, use greater force.
When the greatest force is required, use your head. Surprise is everything. - The Book of Cataclysm