  Three-dimensional (3D) compensated MnBi2Te4 is antiferromagnetic, but
undergoes a spin-flop transition at intermediate fields, resulting in a canted
phase before saturation. In this work, we experimentally show that the
anomalous Hall effect (AHE) in MnBi2Te4 originates from a topological response
that is sensitive to the perpendicular magnetic moment and to its canting
angle. Synthesis by molecular beam epitaxy allows us to obtain a large-area
quasi-3D 24-layer MnBi2Te4 with near-perfect compensation that hosts the phase
diagram observed in bulk which we utilize to probe the AHE. This AHE is seen to
exhibit an antiferromagnetic response at low magnetic fields, and a clear
evolution at intermediate fields through surface and bulk spin-flop transitions
into saturation. Throughout this evolution, the AHE is super-linear versus
magnetization rather than the expected linear relationship. We reveal that this
discrepancy is related to the canting angle, consistent with the symmetry of
the crystal. Our findings suggests that novel topological responses may be
found in non-collinear ferromagnetic, and antiferromagnetic phases.
