One of my favorites. In the movie rampage was red, but the stock color of the toy was yellow. Primed him with flat black, then a thin layer of flat red to produce that old/orangey/dark red look he's got in the movies. Drybrushed him afterwards with aluminum and copper. Also drybrushed his tractor treads with flat earth-copper-and a bit of aluminum. I added some wires and old diodes as accents.
Thanks for viewing!