Exploiting an excellent photocatalyst system with sufficient photogenerated charge separation and strong redox ability for efficient degradation of multiple fluoroquinolones (FQs) antibiotics was crucial but still a big challenge. The significant impacts of novel oxygen-functionalized Ti₃C₂ MXene/exfoliated montmorillonite (Ti₃C₂/MMT_ex) severed as a superior co-catalyst to boost the catalytic activity of single semiconductor was verified in our previous work. Based on that, the Bi₂MoO₆ particles/BiOBr nanosheets were ingeniously anchored onto multilayer O-functionalized Ti₃C₂/MMT_ex by the form of in-situ self-assembly via facile two-step microwave-assisted solvothermal process. Representative characterizations confirmed that Ti₃C₂/MMT_ex exhibited chemical stability and achieved transformation from surface F-terminal to O-terminal owing to the introduction of MMT_ex. Moreover, Ti₃C₂/MMT_ex supporter greatly decreased the accumulation and improved the morphology of Bi₂MoO₆/BiOBr S-scheme heterojunction. With extensive Bi₂MoO₆/BiOBr sheets embedding onto Ti₃C₂/MMT_ex, the quaternary BiOBr/Bi₂MoO₆/Ti₃C₂/MMT_ex catalyst displayed extraordinary coral reef-like structure, followed by abundantly exposing high-active {0 0 1} facets of BiOBr. Furthermore, owing to the Schottky/S-scheme double heterojunction linkage system, the multiple electrons transfer pathways formed over the quaternary composite effectively facilitated the separation of photogenerated charge carriers, thereby leading to the enhanced generation of •O₂⁻ and •OH. Hence, multiple FQs antibiotics degradation efficiency over BiOBr/Bi₂MoO₆/Ti₃C₂/MMT_ex all up to 90%, especially for levofloxacin (LEV), 99% LEV could be eliminated within 120 min. Besides, superior recyclability and stability were revealed in this quaternary composite. Notably, demethylation and piperazine ring-opening dominated LEV degradation pathway and the generated intermediates possessed lower toxicity and ecological risks. Our study further excavates multiple positive effects of Ti₃C₂/MMT_ex co-catalyst in constructing the efficient catalytic system, and supplies novelty tactics to engineer a stable non-noble meta/Bi-based semiconductor Schottky/S-scheme double heterojunction linkage system with compact interface contact.