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We study an axion-like particle (ALP) that experiences a first-order phase transition with respect to its mass or potential minimum. This can be realized if the ALP obtains a potential from non-perturbative effects of SU (N) gauge theory that is confined via the first-order phase transition. Similar dynamics are achieved in the so-called trapped misalignment mechanism, where the ALP is trapped in a false vacuum at high temperatures until it begins to oscillate about the true minimum. The resulting ALP abundance is significantly enhanced compared to the standard misalignment mechanism, explaining dark matter in a broader parameter space that is accessible to experiments eg IAXO, ALPS-II, and DM-radio. Furthermore, the viable parameter space includes a region of the mass m a≃ 10− 8− 10− 7 eV and the ALP-photon coupling g a γ γ≃ 10− 11 GeV− 1 that can explain the recent observation of very high energy …