This 2D companion rebuilds the Barkhausen effect from its actual statistical-physics model instead of animating a stylised domain wall: a flat lattice of spins with random per-site pinning strength and nearest-neighbour ferromagnetic coupling, driven by a slowly sweeping external field. Every spin flips the instant its own local field — external drive plus pinning plus the pull of its neighbours — crosses zero, and because a flip changes the local field felt next door, one small step of the field can cascade into a burst of neighbouring flips: an avalanche, played back as a single click. Sweep the field up from negative saturation to positive and back down and watch the running magnetization trace out a genuinely jagged, history-dependent B-H loop, with the defect-density preset controlling whether jumps come as many small clicks or a few large ones.