The most common and most likely answer to this crossword clue is the 9 letter word AGAMEMNON
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More clues leading to the result AGAMEMNON
- King soon goes round quarry on mare
- Greek leader soon to box willing male
- Hero soon has bold maiden imprisoned
- Willing maiden grabbed by anonymous Greek hero
- Greek hero soon captures willing maiden
- . Old king soon to arrest courageous maiden
- Greek leader soon brought about plucky Priam’s end
- Among men a disturbance reveals old king
- A married man gone abroad to fight at Troy
- Bold maiden interrupts unnamed Greek king
Buddy explains!

The straight part
We know that "Fabled king" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fabled king = agamemnon.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.