Magic words unlocked base, in a mess, surprisingly (4,6)
I believe the answer is:
open sesame
'magic words' is the definition.
(I've seen this in another clue)
'unlocked base in a mess surprisingly' is the wordplay.
I cannot really see how this works, but
'unlocked' could be 'open' (similar in meaning) and 'open' is found within the answer.
'base' could be 'e' (Euler's number - base of natural logarithms) and 'e' is found within the answer.
'a' is present in the answer.
an anagram of 'mess' is 'ssme' which is present in the left over letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for open sesame that I've seen before include "Spell unlocking doors" , "Magic password" , "free entry" , "Spell from Ali Baba and the Forty Thieves" , "Words of Ali Baba" .)