Pedals that stack with the Subdecay Quasar Phaser v4

Fjord Fuzz Berserk

Into a low gain tone, Fjord Fuzz Berserk brings the fuzzy it's missing

Black Arts Toneworks LSTR Fuzz

Run Black Arts Toneworks LSTR Fuzz into that low gain platform and it finally gets some fuzzy

Echoplex EP-3

Run Echoplex EP-3 after Subdecay Quasar Phaser v4 in the signal chain, clear of Subdecay Quasar Phaser v4's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Electro-Harmonix Holy Grail Max

Keep Subdecay Quasar Phaser v4's ambient voice out front: Electro-Harmonix Holy Grail Max goes after Subdecay Quasar Phaser v4 in the signal chain so its spring voice doesn't muddy it — goes in the amp's FX loop (or last, into a clean amp)