Originally Posted by
RanmaBushiko
This is a bit AU already, if you haven't noticed. I've hinted at it, but I'll lay it straight. In this, Gilgamesh beat Arturia completely in the 4th Holy Grail war, and forced her to drink the Mud that came out. It made her mortal, just like planned. However, since he didn't drink it, he's still effectively a mortal Servant. He needs Mana to live. Zouken and Kotomine teamed up in this, rather than Kotomine alone supplying Gilgamesh with Mana, due to the hefty drain of not one, but two different people... and to ensure that it would be natural, Kotomine ordered Gilgamesh and Arturia to help Zouken in any way possible. I was going to cover this in the next tiger dojo, but I was going to hit that over in a much later plot point. Still, for the sake of understanding, I thought I'd explain it now.