Reverb/Resonance pedal schem/vero?

[GammaFlex]

So I'm wanting to build something in the lines of the Last Gasp Misty Cave as seen in this video....

https://www.youtube.com/watch?v=Ed53uohqGbw

I don't mind if it's wacky or a little weird. I'm just looking for something to make some really cool etheral sounds.

Any thoughts?