How does the dragon battle contrast with Beowulf's earlier fights?

In the Old English poem Beowulf, the hero's final battle against the dragon stands in stark contrast to his earlier victories over Grendel and Grendel’s mother.12

While the earlier fights occurred during his youth and showcased his immense strength and prowess, the dragon battle is described as a "long and terrible" struggle that highlights his aging state. Unlike his previous encounters, where he acted as a celebrated champion, this final conflict is marked by a somber, funereal tone as Beowulf faces his inevitable fate, or wyrd.2

Furthermore, the battle emphasizes a painful shift in loyalty: whereas he was previously supported by his peers, all of his retainers desert him in his final hour except for his young kinsman, Wiglaf. Ultimately, while Beowulf succeeds in killing the dragon, the victory is pyrrhic, as he sustains a mortal wound, signaling the end of his life and the beginning of a period of uncertainty for his people.2