  Two photons can annihilate into a neutral pion-like resonance via the anomaly
coupling, just like $\pi^0\gamma\gamma$ in QCD. In some strongly interacting
electroweak symmetry breaking models, e.g., technicolor type models, there
often exist neutral pion-like resonances. TeV photon colliders have a strong
capability to discover such particles, because the standard model background in
photon scattering goes through box diagrams and is therefore highly suppressed.
In this study, we perform a signal-background comparison. We show that $e^+
e^-$ linear colliders running in $\gamma\gamma$ mode can discover such
neutral-pion-like resonances with a decent sensitivity.
