Maschinen Krieger (Ma.K ZBV3000) is a science fiction universe created by Japanese artist and sculptor Kow Yokoyama in the 1980s, currently under development as a Hollywood film by Vertigo Entertainment's Roy Lee. https://en.m.wikipedia.org/wiki/Maschinen_Krieger_ZbV_3000 Fan art.
Also the kröte 3D model was used in the excellent work of the Friendly robot
https://www.artstation.com/artwork/Vyo8LR