Central ideas are the most ideas in a text.

gilgamesh is an epic hero from birth, as he's brought to the world by the hand of several gods who shaped him with the goal of saving humanity. there's a passage from the text that reads "the glorious sun shamash bestowed upon him glory; adad the terrible god of storms bestowed upon him courage. the great gods perfected his magnificence beyond all others, terrible like the great wild bull". this is a great example that show some of the super-human qualities that the gods gave gilgamesh upon his birth.

as gilgamesh grows he has to face many challenges that put his heroism to task. the courage he displays along the way, prove that he's ready to live up to the godly qualities brought upon him. at one point he has to overcome a wild beast by the name of hubamba "whose roar is a flood, whose mouth is fire, whose breath is death", as the text reads. the actions taken by gilgamesh, beating the beast with the use of his super-human force, examplify why he shoud be thought of as an epic hero.

hope this !