Trouble for each major enemy (7)

I believe the answer is:

archfoe

'major enemy' is the definition.
(an archfoe is a main enemy)

'trouble for each' is the wordplay.
'trouble' indicates anagramming the letters.
'for'+'each'='foreach'
'foreach' anagrammed gives 'ARCHFOE'.

I've seen this clue in The Guardian.

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