Pull a flower off, being omnipotent (3,8)
I believe the answer is:
all powerful
'omnipotent' is the definition.
(I know that omnipotent can be written as all-powerful)
'pull a flower off' is the wordplay.
'off' is an anagram indicator.
'pull'+'a'+'flower'='pullaflower'
'pullaflower' anagrammed gives 'ALL-POWERFUL'.
'being' acts as a link.
(Other definitions for all powerful that I've seen before include "Very strong" , "total ability" .)