"As an additional cost to play Grand Gesture, return a Villains United character you control to its owner's hand.
Target defender gets -3 ATK / -3 DEF this attack."

I appologize if this question has been asked before, but I cannot find the answer. Is it true that I can still return a VU character when there is no defender in-play? My reasoning is the 'additional cost' still takes efeect, but the targeting effect get's negated.

I won a game by returning my Zazzala to my hand during the combat phase for that last 2 endurance; yet my opponent said I could not since there was no defender.

You need a legal target to play the card. However, if the target is no longer there after you pay the cost, then the effect is negated.

Which means, if you are being attacked, and you target the characer being attacked [i.e. the defender] and bounced it, the target would no longer be legal, the effect would be negated.

However, you can't play the card without a target. If there is a target, and you play the card, you resolve the 'cost' immediately, before your opponent has an opportunity to 'remove' the defender to prevent the target from being legal.

No.

Its true you pay the cost before your opponent gets a chance to respond, but you can not even play a card if it is not legal to play it. If it requires a target and you aint got one, well juss put it back in yure hand cause I aint even gonna read the cost, effect or nuthin else.

Thanks alot for your help guys, I guess I didn't win that game fairy afterall...=p

unless your opponent had a single attackable character...then you could've just attacked with zazzala and when it became legal used grand gesture...you have your legal target, and you returned ftw...so could you have done that?