Desk twice ransacked — this could not be worse (9)

I believe the answer is:

wickedest

'this could not be worse' is the definition.
(the most evil or wicked)

'desk twice ransacked' is the wordplay.
'ransacked' indicates an anagram.
'desk'+'twice'='desktwice'
'desktwice' is an anagram of 'WICKEDEST'.

(Another definition for wickedest that I've seen is " Most wonderful".)

I've seen this clue in The Guardian.

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