Crossword Genius

Craft is for green aliens (10)

Ross

I believe the answer is:

foreigners

'aliens' is the definition.
(foreigner is a kind of alien)

'craft is for green' is the wordplay.
'craft' indicates an anagram (letters must be crafted into a new form).
'is'+'for'+'green'='isforgreen'
'isforgreen' with letters rearranged gives 'FOREIGNERS'.

I've seen this clue in The Telegraph.
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