Situational warps?

I am somewhat new to the level creator, and unsure of how to work it. I was hoping for help executing a specific Idea I had. Is there a way to make a warp only work after a certain shift has been used?

What I want to use this for is a button that when pressed destroys a major location in my level. I hope to accomplish this by, after the button has been pressed, the screens ajacent to that location now warp Juni to an alternate version of the location which has been destroyed, given the impression that the location really was blown up.

Thank you for your help.

Have a look at this, especially the section on flags.

Thank you for the fast response. The pdf apparently requires a 'master password' to view?

Hmm? Thats strange... There shouldn't be any password.
You should check out Earthbound's seminar then. It covers pretty much everything you need to know.

Thank you, that was very helpful. Cavern Town has been blown to smithereens.

If you're still looking for more on warps/flag warps, you can check out my level, too. Here it is:
http://nifflas.ni2.se/forum/index.php?topic=1366.0