At Intermolecular, we are developing high-throughput techniques to synthesize and characterize materials based on multinary (high entropy) alloys. We use a two-fold approach, using DFT methods to predict single-phase stability, and PVD to synthesize composition spreads in thin (~300nm) films. Magnetic materials are of interest, because intrinsic magnetic properties of a material are similar in thin film as bulk. We have explored a bulk system published by Zhang, Zuo, and Liaw (2015), [CoFeNi]_x-[AlSi]_y (pseudo-binary). In our work we extended this system to a pseudo-ternary, [CoFeNi]x-Al_y-Si_z. Composition, phase, and magnetic properties agreed with published bulk values. Our methodologies were optimized for high-throughput, thus with the generation of three samples we were able to populate the portion of the ternary [CoFeNi]-Al-Si that is bounded by magnetic properties. Intermolecular will also be exploring optimization of magnetocaloric materials using high throughput combinatorial methods, this work will also develop in-situ techniques to characterize magnetocaloric properties.