Ale must affect lucky charms (7)
I believe the answer is:
amulets
'lucky charms' is the definition.
(I've seen this before)
'ale must affect' is the wordplay.
'affect' indicates an anagram (I've seen 'affected' mean this).
'ale'+'must'='alemust'
'alemust' with letters rearranged gives 'AMULETS'.
(Other definitions for amulets that I've seen before include "Ornaments worn as charms against evil" , "Lucky charms" .)