No-good Mussolini's successor reformed game (7)
I believe the answer is:
diabolo
'game' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for diabolo that I've seen before include "Devilish" , "Game involving two sticks joined by a string and a spool-shaped object" , "Top-on-a-string game" , "juggling performance?" , "children's game?" .)