Unseen scenes are unique and out-of-place areas within the layout of a level's terrain, which can't be seen during normal play. This thread is for discussing theories on these hidden areas, sharing new findings, and other such matters.
Here's an example of an 'unseen scene' in Manic Mincers:
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For further info, and more unseen scenes, check out the DKC Atlas Unseen Scenes section.