I want to create a material that blends between two materials in a way that looks as if chunks are falling off. I guess we could use a mask but Im not sture how to use them, I also want to have a slider that is the ammount of one material, overlaying the other
Look into material attributes, material functions and layer blends. As well as material parameters. I’ve only recently started deep diving into the capability of the material editor to make mossy/dirty/bloody variants of some of my environment materials in unreal so I can’t tell you exactly how to do what your asking, but it’s definitely possible. Id start with watching a few tutorials on the features I mentioned