Sabrina sent a telepathic message to Vivian "Viv change into something that would terrify a Duck OK"

she then set off to the place she though her sister would be 

Vivian received the message and thought for a minute. "Aha!" she cried as she quietly turned into a cat. The gaurd duck took one look at her and ran off whimpering. Satisfied, Vivian changed to an elephant and rammed through the bars of the cage. After that, she turned back into a cat, freaking out all the ducks she p*censored*ed. When she neared the entrance, she snapped up an authoritive looking duck with her teeth and carried it outside and to Sabrina. After it was tied up, that's when Sabrina started asking questions...

"It's nothing personal, miss" replied the duck hastily " It's just that you got in the way. We're just trying to destroy your planet, not you in particular."

"Well?" asked Vivian "aren't you going to tell us where you were hired, if not who by?"

"Shut up viv"Sabrina said laughing

"So why our planet ?"sabrina asked the Duck

"Yeah!" said Vivian as she took a silver vile of what appeared to be goop from her bag "Just to be sure he's telling the truth, I'll give him a bit of this" She poured the truth serum down the duck's throat and waitedc for him to get his breath back. "Who are you working for and why?" she asked.

"Retadrox the great!" choked the duck "We have been enslaved by the Retadro curse! We cannot stop working, miss. He is an all powerful sorceror and wants your race gone. My companions are all too happy to give their lives for our master, but I thank you miss, for making me not think the same way! The only antidote to the Retadro curse is that truth serum! Thank you, miss! You are too kind, miss! I am eternally grateful to you, miss!"

"Well that's pretty cool," said Vivian, breaking the silence "I've never had someone eternally grateful to me before. And, as long as Vivian agrees, I think you could come with us and help lead the way to your old master. But if you try any funny business, you'll be dead before you know it."