The Riddler isn’t the only diabolically clever soul in Gotham City. Rocksteady has hidden clues about what Batman would be up to next in each of their Arkham games. We’ve rounded up some of the highlights here.

The first big Easter egg was naturally featured in Batman: Arkham Asylum. When the game was released, Rocksteady hadn’t discussed the direction that a sequel would take. As it turned out, the information was hidden in the game all along. As we mentioned in our video walkthrough, Warden Quincy Sharp’s ambitions went far beyond the walls of the asylum.

To see what exactly Sharp had in mind, players had to access a hidden room in his office. It was invisible to Batman’s best gadgets, so don’t feel like any less of a detective if you never found it. Players had to repeatedly use Batman’s explosive gel on a wall to gain access to the area. Once inside, they could see the reward: a blueprint of a proposed city/prison that sounds familiar to anyone who played Arkham City. The area was so effectively hidden that Rocksteady ended up revealing it several months after Arkham Asylum was released.

When we visited Rocksteady’s offices for our Batman: Arkham Knight cover story, game director Sefton Hill talked to us about Easter eggs in Arkham City. “There was a barge in Arkham City, which was bringing in insects, which are one of the things that Scarecrow uses to create the fear toxin,” he said. “So we were kind of hinting at the fact that he hadn’t been killed by Croc in the first game. That he was still out there and plotting his revenge and taking his time about it.”

Hill and his team may have been overconfident in their abilities to keep things hidden the second time around. “[W]hen we did the barge in Arkham City we were like no one will find this, because you have to be standing in a particular place and use a gadget that there’s no hint you should use,” he said. “And then like one day later it was on YouTube. And we were like, ‘How did that happen?’”

To find the Easter egg, check out this video from Achievement Hunter. It shows the barge, as well as the shipping invoice that points directly to Jonathan Crane bringing large numbers of bugs into town. It lines up perfectly with Arkham Knight’s storyline, in which the Scarecrow threatens Gotham with a toxin attack that forces an evacuation.

In addition to that, intrepid decoders could crack a series of tricky transmissions (clip courtesy of Batman Arkham Videos) to get messages from Scarecrow directly to Batman. “There are definitely hooks in there in those three messages,” says Hill.

The first message reads, “I will return, Batman,” and its follow ups get a little more aggressive. Crane says, “You will pay for what you have done to me,” before sending a third transmission that simply says, “Fear will tear Gotham to shreds.” The codes used increasingly difficult cyphers, and Rocksteady was once again confident that the secret would stay hidden for a while. “I did the codes for those, and I remember talking about it with Nick the audio director and it was just like ‘No one will ever crack those codes, because they’re just ridiculous.’ And I think again that was like a couple of weeks and they were cracked.”

Arkham Knight is the last game in Rocksteady’s Arkham trilogy, so players probably aren’t going to find any hints as to what the Dark Knight will be up to next. That’s not likely to keep players from blasting every wall, scanning every frequency, and giving the world’s greatest detective a run for his money.

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