Being the billionaire that Bruce was he got called to check out something at a lab, and of course he brought the other along, Dick, Jason, Tim, and Damian.

the five entered the lab and were greeted, then told about.. a merman.. a MERMAN?! The five froze before seeing as they walked up to a big tank that almost filled the whole room. The merman had a shiny long tail, and beautiful blue eyes, but he also had fins on his arms that helped with swimming.

They were so surprised, all five.