Who was the greatest of Greek Worriers?

There's no single "greatest" Greek worrier in the sense of a competition. The Greeks didn't have a specific category for "worriers." However, depending on what kind of worrying you mean, different figures might be considered:

* If you mean someone famously plagued by anxiety and indecision: Odysseus from Homer's *Odyssey* is a strong candidate. His long and arduous journey home was filled with perils, and his cleverness was often accompanied by considerable stress and worry about his fate and the safety of his family.

* If you mean someone whose worrying had significant consequences for others: Agamemnon from Homer's *Iliad* could be considered. His leadership in the Trojan War was heavily burdened by difficult decisions and the weight of responsibility, leading to conflict and significant loss of life. His worry about the war's outcome had massive consequences.

Ultimately, the "greatest" is subjective and depends on how you define "worrier." There's no definitive answer.