Arno kept his sword in his back and stayed there with it as the snake kept moving to Fenris movement.

He had to really squint to notice it was Fenris down there. All of the glowing and the odd light made it difficult as it was, and Arno still had to pay attention to his predicament.

The sword only let it bleed some, so Arno had to try to wound it further. The snake tried to shake him off but that was met with Arno forcibly removing the sword and flying above with his wings.

These two were both using what they were "given".