Illusion Walk is an old type of puzzle.  This one of the "trial-and-error" puzzle catagories, because it tricks players thinking that one of the blocks is solid, but it really is a pass-through secret brick. This leads the player into testing every block to see if it is solid or not, then completing the now-revealed platforming. There are two versions of this puzzle: fully black blocks or Secret. Both of them use Secret Bricks
Illusion walk

The puzzle in two versions

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