Doping-based magnetism engineering is an effective approach to synthesize new multifunctional twodimensional (2D) materials from their non-magnetic counterparts. In this work, doping with TMOn clusters (TM = V, Cr, Mn, and Fe; n = 3 and 6) is proposed to induce feature-rich electronic and magnetic properties in a PtS2 monolayer. The pristine monolayer is a non-magnetic semiconductor with an indirect energy gap of 1.81 (2.67) eV as obtained from PBE(HSE06)-based calculations. PtS3-type multivacancies magnetize significantly the monolayer, inducing the emergence of half-metallicity. In this case, a total magnetic moment of 1.90 mB is obtained and magnetic properties are produced mainly by atoms around the vacancy sites. Meanwhile, the PtS2 monolayer is metallized by creating PtS6-type multivacancies without magnetization. Depending on the type of TMOn cluster, either a feature-rich diluted magnetic semiconductor or half-metallic nature is induced, which is regulated mainly by the incorporated clusters. Except for the FeO6 cluster, TM atoms and O atoms exhibit an antiparallel spin orientation, resulting in total magnetic moments between 1.00 and 4.00 mB. Meanwhile, the parallel spin ordering gives a large total magnetic moment of 5.99 mB for the FeO6-doped monolayer. Furthermore, Bader charge analysis indicates that all the clusters attract charge from the host monolayer that is mainly due to the electronegative O atoms. Our results may introduce cluster doping as an efficient way to create new spintronic 2D materials from a non-magnetic PtS2 monolayer.