The avant-garde historically names those artists and movements that intentionally rupture established aesthetic conventions: Futurism’s speed and violence, Dada’s anti-art gestures, Surrealism’s dream logic, and later conceptual art’s dematerialization. “Extreme” as a modifier marks a deliberate intensification of rupture: not just new forms but extremes of scale, sensation, or risk. Where early avant-gardes sought to shock complacency and propose alternatives to bourgeois taste, extreme avant-garde practices escalate shock into endurance, sensation, or technological overwhelm—testing thresholds of taste, ethics, and regulation.