Pedals that stack with the Randall RD20-112 Diavlo 20W 1x12 Combo

Friedman BE-OD

Feed a high gain signal into Friedman BE-OD and it comes out closer to tight

Beetronics Buzzter Boost Preamp

Stack Beetronics Buzzter Boost Preamp on top and a high gain tone tightens toward clean boost

Colorsound Overdriver

Stack Colorsound Overdriver on top and a high gain tone tightens toward clean boost

Electro-Harmonix Deluxe Electric Mistress

Run Electro-Harmonix Deluxe Electric Mistress after Randall RD20-112 Diavlo 20W 1x12 Combo in the signal chain, clear of Randall RD20-112 Diavlo 20W 1x12 Combo's own gain stage

Hungry Robot Moby Dick V2

Put Hungry Robot Moby Dick V2 in Randall RD20-112 Diavlo 20W 1x12 Combo's effects loop, clear of Randall RD20-112 Diavlo 20W 1x12 Combo's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Walrus Audio Fathom

Walrus Audio Fathom's ambient voice goes in Randall RD20-112 Diavlo 20W 1x12 Combo's effects loop — it's not there to compete with Randall RD20-112 Diavlo 20W 1x12 Combo's own high gain character — goes in the amp's FX loop (or last, into a clean amp)

Warm Audio Pedal 76 Compressor

What Warm Audio Pedal 76 Compressor brings here leans toward tight — that's worth building a pairing around