A long narrative poem which deals with heroic deeds is

An epic is a long narrative poem that tells the story of heroic deeds or events significant to a culture or nation. It usually includes a hero, a series of challenges or obstacles, and a resolution. The hero in an epic is often larger-than-life and embodies the values and ideals of the society that produced the work. Epics can be found in many cultures and are often used to express and reinforce cultural identity and values. Examples of famous epics include Homer's Iliad and Odyssey, the Epic of Gilgamesh, and Beowulf.