The battlefield is Ragnarok's. He is in total control of it and it is very large too. It could be as large as he wants it to be or as small as he wishes. It is very large right now because of the titanic octopus within it. The space doesn't seem to have an end and no one can interfere in their fight since it is an enclosed space so he has all day. He stayed out of reach of the tentacles while he sniped at Marlinto with the black beam of devouring.
He can do more damage with his bite and his claws but he is not willing to risk letting Marlinto get his bloody tentacles on him. He might be crushed without being able to fight back. Marlinto is much stronger than him. So being cautious is wise. Except that his current attack is not enough to threaten Marlinto.
