"Natural enemies? The balance of the world?" Muria seemed to ponder. The Giant Dragon is the apex predator within the food chain, but it still exists within that chain.
Therefore, dragons have natural enemies but even if those monsters fond of dragon hunting, once the giant dragon progresses to the ancient dragon stage, they are the ones who get killed, hence, the Giant Dragon doesn't have a literal sense of a natural enemy.
Nevertheless, nature seems unsatisfied with such condition, the power of dragons is built on the plundering of their surroundings, consequently, the deity known as the Giant Dragon Hunter was conceived.
"Like Dragon Hunters?" Muria frowned in thought, "Nature requires balance, many seemingly abhorrent existences, they are indispensable parts of the natural cycle and they are necessary for its existence."