[quote author=M.I.L.F. link=topic=724.msg32262#msg32262 date=1237504401]
But why is that Genesis and Angeal got the wings from the experiments and Sephiroth got them from the lifestream? Where's the logic in that? Unless the lifestream inspired Sephiroth's to grow out or something, but I still think that Jenova would have had some influence, since it influenced the rest of them.
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What do you mean? Sephiroth, Genesis, and Angeal were all born from the Jenova Project. And all three of them sprouted wings just like Jenova. The only difference is when each of them got them. Genesis got his first, and Sephiroth got his last, but that still doesn't change the fact that the unifying factor regarding all three of them is coming from the Jenova Project. Who says Sephiroth's wing came from the lifestream?
Sephiroth's transformation and manifestation of his wing(s) near the end is attributed to him finally becoming one with Jenova in regards to his rebirth. What finally allowed him to regenerate and gain the new body he did at the end was due to the Reunion finally taking place and him absorbing all of the Jenova cells from the Sephiroth copies that made it to the Northern Crater while he absorbed the Lifestream. Furthermore he had Jenova's head with him as well when he fell into the Lifestream and drifted to the Crater.
After all that, not only did he gain his jet black wing, but he also got several angelic wings and a celestial rose halo to boot. I mean, if you look at it that way, Sephiroth's transformation is the most perfect in regards to him becoming closer to being an "angel".
It still all ties back into Jenova being the catalyst and means for Sephiroth to transform and become the perfect "monster" he was destined to be.