All these heroes share the idea of a quest, a long jouirney or a voyage of some kind - whether that be a personal voyage of discovery of self or a physical travelling voyage. Two of the heroes at least share a quest for a particular reason, an ambition which they need to hunt down. Beowulf on the other hand already knows where his intended target lies - but still has a long sea journey or voyage to reach the monster Grendel. No matter - each hero has a goal. Each one also has 'something to face up to - even if that is themselves. In Beowulf's case, he must step up to the plate and face the bloodthirsty monster alone. King Arthur and Beowulf are similar in that they have a band of loyal acolytes to follow them and defend them. Achilles has a weakness he must overcome - and each of the others also has obstacles or hurdles, whether of their making or personality or external.Each one is to a greater or lesser degree - a saga.