Magnetron sputtered freestanding thin films of two modified WE43 alloys (Mg4Y3Nd and Mg4Y3Gd) consist of a supersaturated single phase microstructure with a strong texture in [0001] direction for a wide range of deposition conditions. While the deposition conditions have no significant influence on the corrosion behaviour of these samples, they strongly influence the mechanical properties, which can be tuned between extremely brittle behaviour for high sputtering pressures (2.0 × 10^-2 mbar) and ductile behaviour with a maximum strain of about 18% at room temperature for low sputtering pressures (8.0 × 10^-4 mbar) for both investigated alloys.