Wrathion does, moving closer until their arms brush. It's an unspoken acknowledgement and reassurance both. Of course he'll stay close, of course he'll be here.

"This water is tainted," he murmurs, "but not as much as much as the water which broke through into the arena. It was strongest there."

Where is it coming from? If it's weak here, they're going the wrong direction perhaps. He tenses as the creature recovers from the stagger, and draws his blade as it begins to charge. The idea of running Anduin through, even a doppelganger, makes him uneasy... but, better that than the real one coming to harm.