Malicious sprite associated with verses having repetitious spells? (8)
I believe the answer is:
periodic
'having repetitious spells?' is the definition.
'malicious sprite associated with verses' is the wordplay.
'malicious sprite' becomes 'peri'.
'associated with verses' becomes 'odic' (relating to odes).
'peri'+'odic'='PERIODIC'
(Other definitions for periodic that I've seen before include "every now and then" , "At fixed intervals" , "Recurring at regular intervals" , "Intermittent" , "Occasional" .)