Changing material property does not immediately happen in editor, but it does in a standalone build.

[Kurt-Dekker]

Perhaps you’re modifying a cloned Material value?

Materials materials array of materials renderer:

Generally accessing .material / .materials is going to give you a fresh copy. (See docs for why and when)

Changing material colors was working, now it is not?

This is the problem. You want to either: a) create a fresh array of material references, fill them out with Materials, then assign it back to the renderer OR b) copy out the array, make the changes you want, and put it back. I prefer option b generally, but you may have a reason for the other. It can look something like this: var tmp = new List<Material>( rend.materials); tmp[0].color = ... tmp[1].color = ... tmp[2].color = ... rend.materials = tmp.ToArray(); Or you can use good old Sy…

Adding and removing a material at runtime

If you have an object with multiple Materials, that ALSO implies that the mesh has multiple submeshes. Each Material in the .materials array corresponds to a submesh, so just adding a material to an object isn't likely to do much. If you think you still want to, you need to: create a new blank array of Materials of the right size (+1 or -1 in size) copy the existing Materials out to the correct spot in this temp array add (or omit) the newly added (or removed) material. assign the array o…