Heroic poem and Saga

Heroic poem noun - A long narrative poem telling of a hero's deeds.

Saga and heroic poem are semantically related. in long story topic. In some cases you can use "Saga" instead a noun phrase "Heroic poem".

Saga noun - A narrative telling the adventures of a hero or a family; originally (12th to 14th centuries) a story of the families that settled Iceland and their descendants but now any prose narrative that resembles such an account.

Heroic poem and saga are semantically related. You can use "Heroic poem" instead a noun "Saga".