(From Wikipedia)
The most famous story in which Orpheus figures is that of his wife Eurydice (also known as Agriope). While walking among her people, the Cicones, in tall grass at her wedding, Eurydice ran into a nest of snakes which bit her fatally on her heel. Distraught, Orpheus played such sad songs and sang so mournfully that all the nymphs and gods wept. On their advice, Orpheus traveled to the underworld and by his music softened the hearts of Hades and Persephone (he was the only person ever to do so), who agreed to allow Eurydice to return with him to earth on one condition: he should walk in front of her and not look back until they both had reached the upper world. He set off with Eurydice following and in his anxiety as soon as he reached the upper world he turned to look at her, forgetting that both needed to be in the upper world, and she vanished for the second time, but now forever.
yeah, got the hard achievement. the trick to defeating the black bloons is to put a bunch of tack towers near the beginning and cannons after. also, always have lots of monkeys, and the long range uprgrade usually isnt worth it, except for the super monkey
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