Block

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1. QR code isnt easy to be read
2. is there any hint?

I think i can see what is meant to happen and my B has stuck his head half way into the house but not far enough to trigger claustrophobia. I suspect this instability trick will be very device specific.

Spoiler: Video

Claustrophobia / low ceiling is needed.

@Ray Aznable
Thank you for your reply.
1: using the last level of the operation as a hint, pay attention to the red brick.

2. Finally, B changes the path of LOWCEILING generation by acting as a wall against himself.

I did exactly what you do but on my device didn't worked

My initial attempt was slightly different as i was tapping the entrance block with B on the red brick and B would stall on the second ball, be undecided which way to go and sometimes shoot diagonally straight to the entrance and i hoped would shoot through but never did. I managed the designed win but didn’t like the final move.

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@XSHY ,
@935
thanks for ur unique level design
i found a way to provide
cool looking ball rolling
through unordinary terrains.

Spoiler: Unique Ball Rolling

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@ridgerunner

u make "the red brick"
has more meaning in purpose.
and that sound like it should to be.
as red brick is always special as hint.
so it used for inducting ball to fall
also to reach finish from on top of it.

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5 stars for exploration...

but i suggest to put another
two red bricks
1. below stair
2. infront of tunnel.