Unlocking the full potential of PtNi alloy electrocatalysts for the acidic oxygen reduction reaction (ORR) is significantly restricted by the inevitable dissolution of Ni species. Herein, we present a rational design of tetrametallic PtNiMoRu nanowires (NWs) that decouples the origins of stability and activity via a dual-doping strategy. By coordinating the distinct roles of constituent elements, we demonstrate that Mo doping primarily acts as a lattice stabilizer by increasing the Ni vacancy formation energy to immobilize Ni atoms, while Ru doping optimizes the d-band center of Pt active sites to facilitate intermediate kinetics. Consequently, the optimized PtNiMoRu NWs/C exhibits an exceptional mass activity of 1.04 A mg_Pt^-1 and specific activity of 2.81 mA cm^-2 at 0.9 V vs. RHE, representing 5.2-fold and 8.3-fold enhancements over commercial Pt/C, respectively. Most notably, the catalyst demonstrates superior durability with a negligible half-wave potential decay of only 9 mV after 30,000 accelerated durability test cycles. In a proton exchange membrane fuel cell (PEMFC), this nanowire catalyst delivers a peak power density of 1.18 W cm^-2. This work provides a paradigm for designing durable multi-metallic catalysts by precisely engineering element-specific functionalities within the alloy architecture.