this is the sephiroth i'm on about:
Safer Sephiroth appears as a deformed, tanned, angelic being. He is unclothed, and all of his body below his torso has been replaced by a cloud-like formation with six white wings (two normal ones between two larger ones with decorative frills, and two more at the back) emerging upside-down from where Sephiroth's legs would normally be. There are also two large, free-floating rings on his back, forming a symbol simliar to the Empyrean Halo.
His left arm is normal, but his right arm has been replaced with a large purple, green and red wing, the colors of the Jenova-BIRTH, LIFE, and DEATH bosses.
The image is completed by the background for this battle, which — despite the battle taking place in the bowels of the Planet — is a kaleidoscopic ring of clouds in a blue sky, offering the illusion that the battle takes place in a heavenly plane of existence. This may be a result of the battle taking place within the Holy magic that resided in the background of the former battle, and may serve as yet another allusion to the Celestial Rose: the layout of clouds is reminiscent of past conceptualizations, in which it appeared as a throng of angels encircling a sun-like God, a formation that symbolizes God's perfection and radiance. This imagery is reinforced during the Super Nova attack, as the sun and its shockwave emerge from behind Safer Sephiroth.