Pedals that stack with the Boss FZ-3 Fuzz

Univox Uni-Vibe

Keep Boss FZ-3 Fuzz's fuzzy voice out front: Univox Uni-Vibe goes after Boss FZ-3 Fuzz in the signal chain so its modulated voice doesn't muddy it

Aguilar Octamizer (Bass Octaver)

Put Aguilar Octamizer (Bass Octaver) in front and the fuzzy tone leans further toward octave

Walrus Audio Ages

Walrus Audio Ages stacks clean boost on top of the fuzzy already here

Strymon OB.1 Bass

What Strymon OB.1 Bass brings here leans toward clean boost — that's worth building a pairing around

Walrus Audio Mako D1 High-Fidelity Stereo Delay V1

Run Walrus Audio Mako D1 High-Fidelity Stereo Delay V1 after Boss FZ-3 Fuzz in the signal chain, clear of Boss FZ-3 Fuzz's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Pigtronix Echolution

Keep Boss FZ-3 Fuzz's fuzzy voice out front: Pigtronix Echolution goes after Boss FZ-3 Fuzz 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)