Are the greek gods efficacious

Yes, even Zeus is efficacious. His plan for the Trojan War may be a perfect symbol of his power, but regardless, his carefully laid plans are continually interupted by the chance happenings that never cease to throw wrenches into his most carefully laid plans. In the end, we see that Zeus' plans always work out the way he intended at their conclusion, but that they sometimes had an interesting chain of events that precluded the ending.

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