Pedals that stack with the Rainger FX Air Space Invader 2

Fulltone OF-2 Octafuzz

Fulltone OF-2 Octafuzz stacks fuzzy on top of the mid-forward already here

Catalinbread Katzenkonig

Catalinbread Katzenkonig layers octave onto an already fuzzy signal

Heavy Metal FX HMFX Phase Riot Factory Second

Keep Rainger FX Air Space Invader 2's mid-forward voice out front: Heavy Metal FX HMFX Phase Riot Factory Second goes after Rainger FX Air Space Invader 2 in the signal chain so its modulated voice doesn't muddy it

Pigtronix Echolution

Put Pigtronix Echolution after Rainger FX Air Space Invader 2 in the signal chain, clear of Rainger FX Air Space Invader 2's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Walrus Audio Melee Wall of Noise Black

Keep Walrus Audio Melee Wall of Noise Black after Rainger FX Air Space Invader 2 in the signal chain, clear of Rainger FX Air Space Invader 2's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

W-LM Compression Fracture

What W-LM Compression Fracture brings here leans toward compressed — that's worth building a pairing around