Following a Batman: Arkham Knight Riddler guide is key if you want to reach 100% completion in the game, as Gotham is dotted with a huge 243 Riddler puzzles and it's hard enough just to find them ...

Scan them to solve. Near the center of the port is a squad of Riddler bots in a cage. Use the Voice Synthesizer to order them across the little bridge onto the green smudge. Once they're all in ...