Here's an E minor pentatonic riff that decays over time.  The FB:2 selection in Feedback "degrades the pattern as it repeats"; effectively shuffling the resonant notes around.

The expression pedal fades out the resonance & background reverb.  That brings everything forward for a rhythmic, delay-only decay.  The Feedback setting still shuffles the repetitions around.

Resonance Heel: -10

Reverb Heel:  20

Resonance Toe: 0

Reverb Toe:  0

HotSwitch programming swaps direction of the notes E5-G5-A5-B5 to B5-A5-G5-E5.