Hi! I'm a newbie so don't take any of this too seriously uless someone says it's ok I thought I'd give a try to make a texture that looks a bit like that. It's still pretty far away but I think now it's just a matter of tweaking. The first thing I noticed is that gundam isn't rusty, it just has some parts of missing paint and you can see the metal under it. That's what happens when you fight against other transformers What I did is: 1) unwrap the UV layout 2) Open in photoshop and paint the white and gray textures (diffuse map) 3) downoaded a scratched metal tex from google and filled a new photoshop layer by duplicating that texture all oer the place 3) using a world map as a brush I removed some parts of the "diffuse layer" (so I could see the metal underneath) 4) save diffuse map 5) create a black and white version of it without the painted stuff and changed saturation of the layers 6) saved as bump map 7) added textures in maya 8) render with hdri here's the result and the textures I used (scaled down):