Feat of a magician with a topper or a bowler (3,5)
I believe the answer is:
hat trick
'feat' is the definition.
(I have seen 'Threefold feat' mean 'hat trick' so perhaps 'feat' could also mean 'hat trick')
'magician with a topper or a bowler' is the wordplay.
I cannot quite understand how this works, but
'topper' could be 'hat' (I've seen this in another clue) and 'hat' is found in the answer.
The remaining letters 'trick' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'of a' is the link.
Can you help me to learn more?
(Other definitions for hat trick that I've seen before include "Three goals scored in a game or wickets taken with consecutive deliveries by an individual" , "Run of three successes" , "Three consecutive successes" , "Achievement of three successive victories" , "Taking three wickets with consecutive balls" .)