Final answer:
Yes, it is true that Wonder Woman is turned into a pig by Circe in 'Justice League Unlimited,' and Batman and Zatanna have to solve riddles to transform her back.
Step-by-step explanation:
The question asks whether it is true or false that Wonder Woman is turned into a pig by the sorceress Circe in the show 'Justice League Unlimited,' and Batman and Zatanna have to strike a bargain with Circe in order to transform her back. The answer is True. In the show, Wonder Woman is indeed transformed into a pig by Circe, and Batman and Zatanna have to solve a series of riddles based on Batman's past traumatic events in order to have her turned back into her normal form.