One moment there is no wand, the next moment there is. Bariyan hadn't been paying much attention to that, but he did note it's sudden appearance -- not that he cared. What is it? Just a stick? It isn't until Eridan speaks that Bariyan starts to worry.

He backs away, just a few steps, gaze flicking from Eridan to the wand and back to Eridan again.

"Won't be necessary," Bariyan says. He makes to continue on his way, though he keeps his eye on Eridan at all times.