a comprehensive study.*

Systematic measurements of temperature and magnetic field dependent resistivity and magnetization, and electronic band structure properties obtained from angle resolved photoemission spectroscopy (ARPES) were conducted on high quality single crystals of PdSn₄. We observe that PdSn₄ has anisotropic properties with extremely large magnetoresistance (XMR). ARPES shows interesting surface features near Z and X points, and extensive electronic structure calculations agree well with ARPES. The X point feature corresponds to a gapped Dirac node arc, like observed in PtSn₄. By comparing similar compounds, PdSn₄ and PtSn₄, we address the origin of the XMR in these compounds; neither carrier compensation nor the Dirac node arc surface state appear to be primary reason for the XMR. Additionally, perhaps remarkably, we find that Kohler's rule scaling of the magnetoresistance is obeyed over the full range of temperatures and field strengths that we explore.