This puzzle appeared in Microsoft Puzzle Hunt A, whose theme was Atlantis.
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Hints
Each entry is two clues with their words mixed together and alphabetized. Furthermore, the answers to the two clues are words that differ in exactly one letter, never the first letter.
Each pair of words has a common first letter. Read those letters in order to get a 26-letter instruction.
When the 26-letter instruction refers to pairs, it means the pairs of letters that differ between corresponding words. For instance, for REFUSE/RECUSE, the pair is FC.
There's a single way to reorder the pairs so that the first contains an A, the second contains a B, etc., all the way to Z.