26 cards where the text includes “proliferate” and the color identity ≤ GW and (the card is available on Paper) and it’s legal in Brawl

Adaptive Sporesinger (Phyrexia: All Will Be One #157)
Bloated Contaminator (Phyrexia: All Will Be One #159)
Bloom Hulk (War of the Spark #154)
Cankerbloom (Phyrexia: All Will Be One #161)
Carnivorous Canopy (Phyrexia: All Will Be One #162)
Contagion Engine (Scars of Mirrodin #145)
Contagious Vorrac (Phyrexia: All Will Be One #164)
Copper Longlegs (Phyrexia: All Will Be One #165)
Courage in Crisis (Commander Masters #278)
Evolution Sage (The Lost Caverns of Ixalan Commander #240)
Expand the Sphere (Phyrexia: All Will Be One #168)
Grateful Apparition (Commander Masters #824)
Huatli's Raptor (War of the Spark #200)
Karn's Bastion (The Lost Caverns of Ixalan Commander #339)
Martyr for the Cause (War of the Spark #23)
Metastatic Evangel (Modern Horizons 3 #35)
Planewide Celebration (War of the Spark #172)
Pollenbright Druid (Commander Masters #312)
Proud Pack-Rhino (Modern Horizons 3 #41)
Smell Fear (Modern Horizons 2 #173)
Staff of Compleation (Phyrexia: All Will Be One #242)
Thirsting Roots (Phyrexia: All Will Be One #185)
Unnatural Restoration (Phyrexia: All Will Be One #191)
Urban Daggertooth (Modern Horizons 2 #181)
Venomous Brutalizer (Phyrexia: All Will Be One #193)
Wanderer's Strike (Commander Masters #69)

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