Ah well, was hoping for another post from Corai over the night, but in order to get the thread going again, I'll post the ending of the fiasco.
The Zanzetkukens clashed on the mountaintop for what seemed like years. The dark Zanzetkuken was slowly, incrementally gaining the upperhand. The normal one realized this as they locked blades, again. He (regular) could see no way out where he would secure victory. He clashed with his dark self a few more times before they broke off, and he saw what needed to be done. He moved forward, seemingly going to lock blades with his dark self, but instead, he sheathed his sword, dodged under the dark blade, grabbed onto the Dark Zanzetkuken, and threw them both off the mountain. After the shock wore off, the Dark Zanzetkuken tried to save himself, but Zanzetkuken (regular) stabbed him (dark) with his blade. They had reached the mountain falls at that point and fell towards the multitude of rocks made of sharp obsidian when the Dark Zanzetkuken finally died of the wound inflicted by the blade. Zanzetkuken mentally recorded a few messages on some blank crystals within the room of the Slashdiver where Hugo and Corai learned of the phyrexians, namely, a message to the general and his last will. With that, a peace came over him as he fell into the rocks below.
The Dark Zanzetkuken had linked the evolved form of phyrexis to himself. While it did make the strain far stronger, it also left a weakness. If he died, the phyrexis died. All across the multiverse, wherever the evolved strain was, the nanites died, returning their hosts to their pre-infected forms...
Soon after the battle for the citadel, the general walked into the information room*, attempting to find out why the battle had ended with the phyrexis dying, when he saw that a crystal was already in the pedestal in the center of the room. He viewed the message that was left for him, then went up to the bridge, and said, "Plot a course for the twelfth bay."
"Sir."
At the twelfth bay, the Slashdiver landed a short distance away, and a small delegation came out from it, intending to meet with the survivors, and bring whatever aid was needed. Guards were placed at the entrance of the Slashdiver, and would only allow in whoever was allowed in by the delegation.
I appologize if you do not like the writing, because I just now came up with most of the details. The souls of the worlds hint was scrapped from this, when I couldn't think of a way to incorporate them at the time of writing.
Note: the scenery was there to allow an easier access to the mana type it embodied
*will be changed.