Fake walls (NSMBWii/NSMBU)

[MrPunchia]

R'ember in New Super Mario Bros. Wii and U, when you'd find secret areas behind walls? Basically, if you didn't know, there are some secret areas in those games that masquerade themselves as solid terrain, when in reality, they're fake walls that, when Mario enter the areas, this happens...

Spoiler

There was a LunaLUA API made for SMBX2 that accomplished this by making the fake walls into an individual layer (a hidden layer btw) that turned every block placed on that layer into a fake wall. If there's any way to make this work, I'd definitely want it done this way.

[Luna]

You can easily make this by using events.

[Ariinui]

yup here'S 2 things that can help you
viewtopic.php?f=29&t=290&p=1756#p1756
viewtopic.php?f=65&t=2062&p=13815#p13815