Colour changes, transforming clothes and a great theme. No wonder this mermaid/teen doll was the favourite Barbie tested this year. Our testers didn't need to see the new Barbie movie to LOVE Merliah. There are so many amazing things about this doll... For starters, there's the cool colour changes that actually work - especially the nail polish, but the pink hair streaks and extra tattoo detailing were also big hits. Even the clothing design gets A+ marks: a mermaid tail that flips up into a teen hoodie. And then, there's the whole mermaid theme - perfect for the bath, which is, after all, where so many Barbies like to spend time.