That's definitely Ariel on the header card. These green/aqua/white Vacor marbles have been designated "Troll" in the UK and at least a few other countries. I suspect that FS-USA/Mega Fun decided to market them as "Mermaid" in the states in order to give girls some more clearly feminine choices (along with the "Unicorn" and "Princess" varieties which were released alongside Mermaids in 2014). They have a very attractive color pattern! Not as eye-popping as some Vacor color schemes, but a very solid aesthetic call.