I know going ahead that this will be nitpicky, but your comment strikes me as absurd.
Keeping in mind that there are people who believe there was a male God who bet a Giant the Giant could not build a wall in an allotted time, and then, when it looked like the Giant would win the bet, the God turned into a female horse so he could seduce the Giant's magic stallion, causing the Giant to lose the bet and the God to become impregnated and give birth to a magical, 8-legged horse...
Keeping in mind there are people who believe that there was a God who turned himself into a swan so he could make love to a woman...
Keeping in mind all the myths out there, the one you deem "of the more ludicrous" is a big flood??
And Surrealist literature proves that assertion wrong.
At last all of those use limited magic. The flood story takes an endless series of magical events and then God has to go out of his way to hide the flood in a process that took generations if one wants to claim that it is true. The flood myth requires a dishonest version of God. Now Zeus was almost human in his attributes so him being dishonest at times only adds to his being a myth. Does God being dishonest in regards to the flood myth make him mythical?