I have not finished Aquila so I am not sure if there is a turret there but if there is not, a turret in the form of mermaids would be cool. In the Odyssey, a very old epic poem, Odysseus is lured to mermaids while on his ship because they make such beautiful music. But when you are lured to the mermaids, they attack you. Don't you think that would go for an awesome turret? When you are near the mermaid turret, you will hear calming voices singing, but when you get close them, They start attacking with whirlpools similar to the sirens storm school card in Wizard101.