The spontaneous conversion of muonium to antimuonium is one of the interesting charged lepton flavor violation phenomena, offering a sensitive probe of potential new physics and serving as a tool to constrain the parameter space beyond the Standard Model. Utilizing a high-intensity muon beam, a Michel electron magnetic spectrometer and a positron transport solenoid together with a positron detection system, Muonium to Antimuonium Conversion Experiment (MACE) aims to discover or constrain this rare process at the unprecedented level. Meanwhile, the muon intensity frontier will also drive the detection technology across the road such as muSR and muography.