To achieve different colored outer glows for your magic balls in Unity, you can use emission maps combined with MaterialPropertyBlocks. First, ensure that your emission map is set up to cover only the areas you want to glow. Then, in Unity, you can use a MaterialPropertyBlock to change the emission color for each skin dynamically. This allows you to adjust the color of the emission without creating multiple material instances. You can set the emission color in the MaterialPropertyBlock to match the desired glow color for each skin, and apply it to the renderer of your character.