Pedals that stack with the Beetronics Swarm Fuzz Harmonizer

Zvex Seek Trem

Put Zvex Seek Trem after Beetronics Swarm Fuzz Harmonizer in the signal chain, clear of Beetronics Swarm Fuzz Harmonizer's own gain stage

Aguilar Octamizer (Bass Octaver)

Aguilar Octamizer (Bass Octaver) layers octave onto an already fuzzy signal

Fender Blender

Fender Blender stacks octave on top of the fuzzy already here

Walrus Audio Melee Wall of Noise Black

Run Walrus Audio Melee Wall of Noise Black after Beetronics Swarm Fuzz Harmonizer in the signal chain, clear of Beetronics Swarm Fuzz Harmonizer's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Hungry Robot The Borderland

Keep Beetronics Swarm Fuzz Harmonizer's fuzzy voice out front: Hungry Robot The Borderland goes after Beetronics Swarm Fuzz Harmonizer in the signal chain so its modulated voice doesn't muddy it — goes in the amp's FX loop (or last, into a clean amp)

PRS Mary-Cries Compressor

PRS Mary-Cries Compressor leans toward clean boost, and that's a real, usable character to pair with