Both are characters I'm acknowledged at. Pain would win, I'm saddened to say. Deva's powers are almost invincible, and Onoki cannot counter CT nor CST; even both are restricted, I fail to see how he wins. His best offense which consumes lot of Chakra is absorbed by Preta Path, as forecast by Edo Madara, and his best defense will be wrecked by constant attacks of Asura Path. I can see him standing a chance if he splits their teamwork by Doton Clones, but that's negative on him due to dividing his Chakra, which I don't believe will allow him to utilize his full potential.