Making comeback in cartoon? A Tasmanian devil! (5)
I believe the answer is:
satan
'devil' is the definition.
(synonyms)
'making comeback in cartoon? a tasmanian' is the wordplay.
'making comeback' is a reversal indicator.
'in' indicates the answer is hidden within the clue.
'natas' is hidden within 'cartoon a tasmanian'.
'natas' back-to-front is 'SATAN'.
(Other definitions for satan that I've seen before include "Apollyon" , "Fallen archangel" , "The devil, Beelzebub" , "Old Nick, Lucifer or Beelzebub" , "arch-fiend" .)