Limitless.

If anyone cares about the plane enough to want to stop him then they will come to fight him. He doesn't need to go looking for them so he made himself comfortable in the center of the all-devouring whirlpool. He said to himself, "It is a pity really. To be a dragon and to be the weakest one. But Legion-8 will never have that problem."

The fountain of life is a majestic dragon. But it is giving up. It is not just giving up the fight, it is giving up its hope and its future. It is a dragon of life and it wants to strengthen itself. So it combined the law of creation with its divine ability. 

That was too much for its dragon heart to bear so now it needs the life crystal that Mother High Heaven used to seed the plane, supply mana at the beginning of the plane, and manipulate life within the plane to strengthen its inner world.