Click HERE to see this thread with all of the graphics, features, and links.

who wins?

parallax

At their peaks they both had more or elss the same power levels (all the energy of Oa), and were basically god-like and could do nigh anything (Parallax for example was on a mission to destroy, and then remake, the universe in his own image).
However I'd say Parallax was stronger.
Why?
Well, Hal Jordan has a higher will power than Rayner, plus Hal was absolutely insane at the time.
Parallax would most probably win.

No he wouldn't. Kyle Rayner as GL was standing up to Hal better than anyone. The only way you could pick one or the other is if you were biased towards Hal or Kyle.

Logically they should stalemate everytime.

I thought Kyle was actually supposed to be more powerful... Something with his ring. And assuming that the Oa power battery gets duplicated, I'd still say Kyle. Hal is more powerful as GL because of his willpower, but I don't know how much of a factor that would be, seeing as they both now command nearly limitless power. Kyle always got by because of his creativity and intelligence, which I think would mean even more here than it does with the rings.

Kyle's ring was powerful because of the Ion energy he had been tapping into. What had happened to Kyle and his ring was that when he reabsorbed Oblivion into himself, the energy that made up Oblivion moved on to find the power source of the Green Lantern. "Oblivion" found the energy Hal had left behind when he sacrificed himself to reignite the sun and recreate Oa. The Oblivion energy and residual energy Hal left behind combined and began to grow. When Kyle reabsorbed Oblivion to himself he kept a connection to the energy that made up Oblivion and was now able to tap into what he called "Ion" using his ring.

The Oan energy itself is supposed to be infinite since it's the sum of the willpower of every living being in the universe.

ion. as much as i like hal, ion would still win.

Parallax would win, as ION was created from the left over severely depleted energy of the dead Hal Jordan Parallax.

Oblivion and Nero caused the energy to grow back to its former level. Kyle absorbed both of them into his being.

Originally posted by The Ion
Oblivion and Nero caused the energy to grow back to its former level. Kyle absorbed both of them into his being. Nero was feeding off the Kyle's ring that was feeding off of Parallax's energy. And Oblivion was a childhood comic he wrote that turned real because of tapping into the power subconsciously. However, that's still not as powerful as Hal was after absorbing all the energies of OA/Antimonitor and other sources as he did. Most of the energy was already gone after the Crisis in Time let alone when Hal died....ION was powerful indeed, but not quite that level, IMO.

parallex

Parallex wins because ......well he just wins okay.

Originally posted by Juntai
Nero was feeding off the Kyle's ring that was feeding off of Parallax's energy. And Oblivion was a childhood comic he wrote that turned real because of tapping into the power subconsciously. However, that's still not as powerful as Hal was after absorbing all the energies of OA/Antimonitor and other sources as he did. Most of the energy was already gone after the Crisis in Time let alone when Hal died....ION was powerful indeed, but not quite that level, IMO.
The energy from Oblivion and Nero caused the energy to grow once Kyle absorbed it. Furthermore, Kyle stated specifically the energy grew everytime he tapped into it both before and after he claimed all of it. This is why he was able to recreate every single Guardian as well as power the new GLC (7200 strong). If the energy was depleted, that wouldn't have been possible.