Heroic tales involving palindrome (5)
I believe the answer is:
sagas
I believe this clue is a double definition.
'heroic tales' is the first definition.
(saga is a kind of heroic tale)
'palindrome' is the second definition.
'involving' is the link.
(Other definitions for sagas that I've seen before include "Tales of heroes" , "Myths" , "Long involved stories" , "Heroic tales" .)