Top Voted Answer
Yeah, there's a few that have been discovered. SPOILERS!
If you go back to the Joker's room in the Steel Mill after the game and look on the floor next to Harley's costume, you'll find a pregnancy test that reads positive. Also, if you beat the game on New Game +, you hear Harley singing a twisted lullaby to a child. The best easter egg is located on a ship near the bridge to the Steel Mill (that has the Scarecrow mask and hay on the top of it). Part of the ship is raised slightly, like a hatch. If you stand on it in the right spot and use your crypto sequencer, you'll get a very difficult combination to break. If you do it, there's a neat little area down there with some interesting surprises...zoom in on the thug at the end and read the invoice on a pillar! MegaManZ3ro (Expert) - 6 years ago
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