Hey everyone

I have started learning Houdini this year. As you can see in the attachments the staircase is visible the entire time, but I only want it to be revealed as the effect travels up the path. I have tried attribute promote and attribute wrangle after some research but still couldn't get them to work, I'm sure I was just using them wrong.

Any help will be greatly appreciated.
Thanks!

You'll get useful answers if you can post a hip file and any dependencies. Nobody can really tell what you're doing wrong just by looking at the node network.