While the signature indentations in walls had previously been spotted in the gameplay trailers released thus far, Secret Bases have been officially confirmed to be making a comeback in OmegaRuby and AlphaSapphire!
Now referred to as Super-Secret Bases, they are made in the same fashion as before, using Secret Power on special walls and trees. You can still share your Super-Secret Base with others, but they now utilize the 3DS' camera and wireless instead of having to mix records to let you share QR codes and tag people with StreetPass. You can talk to the person inside their Base to invite an NPC version of them back to yours, allowing you to battle, use special skills such as an instant level-up or faster egg hatching, and receive more decorations. You can level up your Base by capturing the flag found in other Bases, which increases the power of special skills. It is also teased that you can turn your Base into somewhat of a Gym by setting battle rules, but this has yet to be expanded on.
https://www.youtube.com/watch?v=etj4Po0--QM
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