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The discovery of Weyl semimetals (WSMs) has fueled tremendous interest in condensed matter physics. WSMs require breaking either inversion symmetry (IS) or time-reversal (TRS); they can be categorized into type-I and type-II WSMs, characterized by un-tilted strongly tilted cones respectively. Type-I with IS TRS have been realized experimentally, but TRS-breaking WSM still remains elusive. In this article, we report an ideal only one pair nodes observed the antiferromagnetic topological insulator Mn(Bi1-xSbx)2Te4 under magnetic fields. This state is manifested a large intrinsic anomalous Hall effect, non-trivial $\mathrm{{\pi}}$ Berry phase cyclotron orbit positive magnetoresistance ferromagnetic at optimal sample composition. Our results establish promising platform for exploring physics underlying long-sought, WSM.