Hector and Achilles are fighting in a war against a real human enemy although assisted by gods while Beowolf and Grendel fight supernatural powers.
Explanation:
Heroes Hector and Achilles are close friends on the battlefield of Troy fighting for the Greeks in the war. They are facing human enemies although both sides are assisted by the Gods.
In Beowulf and Grendel, the fight is with supernatural powers and own mortality of the two and there is no direct godhead powers that help them as such.
In both the stories the sidekick dies inspiring the main hero to take the journey or the war as personal.
