You can get the material or make one yourself with Ryan King's tutorial.
You can now make your Blender objects get moldy with this handy animated procedural mold material created by talented artist Ryan King.
The location of the mold can be changed by scaling and moving the empty object. You can also animate the location of the empty to make the mold grow.
If you purchase the pack, you will also get procedural orange peel material and a Blender file with moldy bread.
Contents of the package:
● Procedural Mold Blender File
● Procedural Mold Blender File-Animated (With Orange Material)
● Moldy Bread Blender File (With Procedural Mold)
● Bread Normal and Color Maps
● Final Renders
● Mold Growing Animation
● HDRI Lighting
And if you'd like to create the material yourself, Ryan King provided a tutorial on how to do it:
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