yes we only saw three SS class demons actually i think raizen in his prime would of been the only SS class demon but theres demons much stronger than that infact if you go deep enough into makai you will find SSSSS class demons
Saints' power originated from the understanding of the “Cosmo”. Everything in the universe is made up of particles. And the origin of the universe and everything in it is tied in with the Big Bang. The Saints take this knowledge to another level: humans are made of particles, thus humans should be able to use the mysterious forces behind the particles. This is because, the energies of the Big Bang still reside within all particles.
Each atom within a human body resembles a small solar system, and since the human body consists of billions of atoms, the totality forms a “small Cosmo” or a “Micro Universe”. Each person’s Cosmo has its own unique signature. If permission is granted, one can also draw another’s Cosmo to amplify one’s own Cosmo. The power of the Cosmo can also be channeled through: Their designated constellation, the Saints' Cloths, armors given by gods to mortals.
The Saints go through extensive training, to harness, unleash and control its Cosmo Power. However it is only released in a condensed form, upon the designated target. Reason for this, is because the Saint attempt is sub-atomic destruction on the isolated target.
Nothing seems to be out of Cosmo’s reach. It has bin shown to resist reality warp, matter transmutation, physical destruction, and effect intangible objects such as the spirit, soul, energy, curse, light etc…
The 9th sense...
The 9th sense lies farther beneath the 8th pervious ones. I have no concreted explanation over the 9th sense. However I shall give a small theory of mine backtracking the manga. The 9th sense is wielded by the Gods, it the highest possible standard one can reach period; that much I do now. This must be the so called “Miracle” the Gold Saints speak of, and the power to rival Gods that Saori explains to Seiya at the end of the Manga (yet it is not referenced as the 9th sense, just some what tied in). Its when a Saints Cosmo reaches critical mass, and expends without limit. Yet is able to harness it, this explains why their cloths go to a final Transformation that only the Olympic Gods could wear (not even minor Gods are qualified), yet a Cosmo of the same caliber is needed to wear the Kamui. We then again see Seiya at the end of Overture attain a power that rivals Apollo (another Olympic Champion). Seiya mentions that his Micro Cosmo can be raised to limitless ends, to the point of becoming one with the universe itself.
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